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.
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The experimental proton resonance data for the reaction P+48Ti have been used to calculate and evaluate the level density by employed the Gaussian Orthogonal Ensemble, GOE version of RMT, Constant Temperature, CT and Back Shifted Fermi Gas, BSFG models at certain spin-parity and at different proton energies. The results of GOE model are found in agreement with other, while the level density calculated using the BSFG Model showed less values with spin dependence more than parity, due the limitation in the parameters (level density parameter, a, Energy shift parameter, E1and spin cut off parameter, σc). Also, in the CT Model the level density results depend mainly on two parameters (T and ground state back shift energy, E0), which are app
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The aim of this research is to estimate the parameters of the linear regression model with errors following ARFIMA model by using wavelet method depending on maximum likelihood and approaching general least square as well as ordinary least square. We use the estimators in practical application on real data, which were the monthly data of Inflation and Dollar exchange rate obtained from the (CSO) Central Statistical organization for the period from 1/2005 to 12/2015. The results proved that (WML) was the most reliable and efficient from the other estimators, also the results provide that the changing of fractional difference parameter (d) doesn’t effect on the results.
16S ribosomal RNA (16S rRNA) gene sequences used to study bacterial phylogeny and taxonomy have been by far the most common housekeeping genetic marker utilized for identification and ancestor determination. This study aimed to investigate, for the first time, the relationship between Klebsiella spp. isolated from clinical and environmental samples in Iraq.
Fifty Klebsiella spp. isolates were isolated from clinical and environmental sources. Twenty-five isolates were collected from a fresh vegetable (Apium graveolens) and 25 from clinical samples (sputum, wound swab, urine). Enteric bacteria were isolated on selective and differential media and identified by an automatic identif
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This research involves the application of spectral indices and GIS techniques coupled with the Analytic Hierarchy Process, to assess Baglia site, eastern Missan, as a water harvesting potential site. The AHP and pairwise comparison have been used through select four criteria including TWI, TRI, MNDWI, and NDSI, which were deemed as impact factors for this study. All these criteria have been weighted according to their significance in the water harvesting system. The findings of the AHP analysis method explained that the WH potential zones in Baglia site were divided into three zones, namely, high, medium, and low suitability. The findings demonstrate that Bglia site, where the highly appropriate zone is located in the deep v
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The aqueous extract of milk thistle (Silybum marianum) leaves as a green corrosion inhibitor for AA7051 aluminum alloy in sodium hydroxide solution was investigated at a range of temperatures. Potentiodynamic polarization findings exhibit a mixed–type inhibitor with directly increased inhibition efficiency with the concentration of inhibitor. The adsorption of the inhibitor on aluminum alloy obeys Langmuir isotherm and the kinetic as well as thermodynamic parameters were measured and discussed.
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In this study water-soluble N-Acetyl Cysteine Capped-Cadmium Telluride QDs (NAC/CdTe nanocrystals) using N-acetyl cysteine as a stabilizer were prepared to investigate the utility of quantum dots (QDs) in distinguishing damaged DNA, (extracted from blood samples of leukaemia patients), from intact DNA (extracted from blood samples of healthy individuals) to be used for biosensing application. Based on the optical characterization of the prepared QDs, the XRD results revealed the formation of the NAC-CdTe-QDs with a grain size of 7.1nm. Whereas, the SEM test showed that the spherical size of the NAC-CdTe-QDs lies within 11~33nm. NAC-CdTe-QDs have superior PL emission properties at of 550nm and UV-Vis absorption peak at 300nm. The energy gap
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Abstract
This study aims to find the relationships between social capital (social network, social trust, shared goals) and knowledge sharing (knowledge Donating, knowledge collecting) as independent variables and their impact on improving the quality of educational services (academic staffs quality, Quality of teaching methods and study curriculums). This research is an important, because it attempts to identify the relationship between social capital and the knowledge sharing and their effect on improving the quality of educational service for universities. The study problem was determined in several questions related to the nature of the correlation relationship - the impact between the different independent variables (
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