Preferred Language
Articles
/
alkej-315
High Order Sliding Mode Observer-Based Output Feedback Controller Design For Electro-Hydraulic System
...Show More Authors

A perturbed linear system with property of strong observability ensures that there is a sliding mode observer to estimate the unknown form inputs together with states estimation. In the case of the electro-hydraulic system with piston position measured output, the above property is not met. In this paper, the output and its derivatives estimation were used to build a dynamic structure that satisfy the condition of strongly observable. A high order sliding mode observer (HOSMO) was used to estimate both the resulting unknown perturbation term and the output derivatives. Thereafter with one signal from the whole system (piton position), the piston position make tracking to desire one with a simple linear output feedback controller after canceling the perturbation term.

The numerical simulation results showed excellent performance of the proposed output feedback controller in forcing the piston position to follow the desired reference position. Moreover, the control effort spent was minimal.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Multi-Dimensional Angle of Arrival Estimation by Circular Phased Adaptive Array Antennas
...Show More Authors

In this paper the use of a circular array antenna with adaptive system in conjunction with modified Linearly Constrained Minimum Variance Beam forming (LCMVB) algorithm is proposed to meet the requirement of Angle of Arrival (AOA) estimation in 2-D as well as the Signal to Noise Ratio (SNR) of estimated sources (Three Dimensional 3-D estimation), rather than interference cancelation as it is used for. The proposed system was simulated, tested and compared with the modified Multiple Signal Classification (MUSIC) technique for 2-D estimation. The results show the system has exhibited astonishing results for simultaneously estimating 3-D parameters with accuracy approximately equivalent to the MUSIC technique (for estimating elevation and a

... Show More
View Publication Preview PDF
Publication Date
Sun Dec 27 2020
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Phytochemical Investigation of Aerial Parts of Iraqi Cardaria draba
...Show More Authors

 The aim of this study was to study chemical constituents of aerial parts of Cardaria draba since no phytochemical investigation had been studied before in Iraq. Aerial parts of Cardaria draba were defatted by maceration in hexane for 72 h. The defatted plant materials were extracted using Soxhlet apparatus, the aqueous Methanol 90% as a solvent extraction for 18 h, and fractionated with petroleum ether- chloroform (CHCl3)- ethylacetate- and n-butanol respectivly. The ethyl acetate, n-butanol, and n-butanol after hydrolysis fractions were investigated by high performance liquid chromatography (HPLC) and thin-layer chromatography (TLC) for its phenolic acid and flavonoid contents. Flavono

... Show More
View Publication Preview PDF
Scopus (8)
Crossref (1)
Scopus Crossref
Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Engineering
THEORETICAL AND EXPERIMENTAL STUDY ON THERMAL PERFORMANCE OF CLOSED WET COOLING TOWER
...Show More Authors

Thermal performance of closed wet cooling tower has been investigated experimentally and theoretically
in this work. The theoretical model based on heat and mass transfer equations and heat and mass transfer balance equations which are established for steady state case. A new small indirect cooling tower was used for conducting experiments. The cooling capacity of cooling tower is 1 kW for an inlet water temperature of 38oC, a water mass velocity 2.3 kg/m2.s and an air wet bulb temperature of 26oC. This study investigates the relationship between saturation efficiency, cooling capacity and coefficient of performance of closed wet cooling tower versus different operating parameters such wet-bulb temperature, variable air-spray water fl

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Feb 10 2023
Journal Name
Journal Of Applied Mathematics
The Dynamics of a Delayed Ecoepidemiological Model with Nonlinear Incidence Rate
...Show More Authors

In this paper, the general framework for calculating the stability of equilibria, Hopf bifurcation of a delayed prey-predator system with an SI type of disease in the prey population, is investigated. The impact of the incubation period delay on disease transmission utilizing a nonlinear incidence rate was taken into account. For the purpose of explaining the predation process, a modified Holling type II functional response was used. First, the existence, uniform boundedness, and positivity of the solutions of the considered model system, along with the behavior of equilibria and the existence of Hopf bifurcation, are studied. The critical values of the delay parameter for which stability switches and the nature of the Hopf bifurcat

... Show More
View Publication Preview PDF
Scopus (8)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Wed Mar 15 2023
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of a novel coating material on the microleakage of glass hybrid restoration in primary teeth – An in vitro study
...Show More Authors

Background: Glass ionomer restorations are widely employed in the field of pediatric dentistry. There is a constant demand for a durable restoration that remains functional until exfoliation. This study aimed to measure and compare the effect of a novel coating material (EQUIA Forte Coat) on the microleakage of glass hybrid restoration (EQUIA Forte HT) in primary teeth. Material and method: Thirty cavitated (class-II) primary molars were allocated randomly into two groups based on the coat application; uncoated (control) and coated group (experimental). Cavities were prepared by the use of a ceramic bur (CeraBur) and restored with EQUIA Forte HT with or without applying a protective coat (EQUIA Forte Coat). Samples went through the therm

... Show More
View Publication Preview PDF
Scopus (2)
Crossref (1)
Scopus Crossref
Publication Date
Mon Feb 01 2016
Journal Name
Journal Of Engineering
Environment Friendly Eco - City
...Show More Authors

The World witnessed over the past few decades a clear change in the urban existence map, where the number of cities' residents has increased and the cities geographic area expanded, also networks of roads and electric power stations were spread. This extraordinary events caused the drawing of a different identity to the world, race with itself in the field of energy and raw materials consumption. Therefore, the research issue individualizes in the lack of available knowledge concerning the subject of environment friendly ecological urban desiging and planning.So the research aims to define the environmentally friendly eco-city' structural elements and to clarify their most important planning and design foundations. To In

... Show More
View Publication Preview PDF
Publication Date
Mon Jul 01 2024
Journal Name
المجلة العلمية لعلوم وفنون الرياضة
العلاقة بين طول الذراع وبعض المتغيرات البايوكينماتيكية في سباحة الفراشة (50 متر) لسباحي المنتخب الوطني
...Show More Authors

Competitive swimming is a highly researched area and technological developments have aided advances in the understanding of the biomechanical principles that underpin these elements and govern propulsion. Moreover, those working in the sports field especially in swimming are interested in studying, analyzing, evaluating and developing motor skills by diagnosing the strengths and weaknesses of the skill, and accordingly, coaches and specialists correct these errors. The researchers chose this (Butterfly swimming) and the (arm length) is an important variable because the success of the stroke is greatly dependent on the propulsion generated from the arm pull, and swimmers with a longer arm span have a mechanical advantage with the resulting f

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Nov 02 2013
Journal Name
International Journal Of Computer Applications
Mixed Transforms Generated by Tensor Product and Applied in Data Processing
...Show More Authors

Finding orthogonal matrices in different sizes is very complex and important because it can be used in different applications like image processing and communications (eg CDMA and OFDM). In this paper we introduce a new method to find orthogonal matrices by using tensor products between two or more orthogonal matrices of real and imaginary numbers with applying it in images and communication signals processing. The output matrices will be orthogonal matrices too and the processing by our new method is very easy compared to other classical methods those use basic proofs. The results are normal and acceptable in communication signals and images but it needs more research works.

View Publication
Crossref
Publication Date
Sun Jan 12 2014
Journal Name
International Journal Of Current Engineering And Technology
The Effect of Sb Dopant and Annealing Temperature on the Structural and Optical Properties of GeSe Thin Films
...Show More Authors

The pure and Sb doped GeSe thin films have been prepared by thermal flash evaporation technique. Both the structural and optical measurement were carried out for as deposited and annealed films at different annealing temperatures.XRD spectra revealed that the all films have one significant broad amorphous peak except for pure GeSe thin film which annealed at 573 K, it has sharp peak belong to orthorhombic structure nearly at 2θ=33o. The results of the optical studies showed that the optical transition is direct and indirect allowed. The energy gap in general increased with increasing annealing temperature and decreased with increase the ratio of Sb dopant. The optical parameters such as refractive index, extinction coefficient and real and

... Show More
View Publication Preview PDF
Publication Date
Tue Oct 01 2019
Journal Name
Journal Of Engineering
Mechanisms of Plant-Correlation Phytoremediation of Al-Daura Iraqi Refinery Wastewater Using Wetland Plant from Tigris River
...Show More Authors

In developing countries, conventional physico-chemical methods are commonly used for removing contaminants. These methods are not efficient and very costly. However, new in site strategy with high treatment efficiency and low operation cost named constructed wetland (CW) has been set. In this study, Phragmites australis was used with free surface batch system to estimate its ability to remediate total
petroleum hydrocarbons (TPH) and chemical oxygen demand (COD) from Al-Daura refinery wastewater. The system operated in semi-batch, thus, new wastewater was weekly added to the plant for 42 days. The results showed high removal percentages (98%) of TPH and (62.3%) for COD. Additionally, Phragmites australis biomass increased significant

... Show More
View Publication Preview PDF
Crossref (5)
Crossref