Preferred Language
Articles
/
alkej-300
Design and Simulation of L1-Adaptive Controller for Position Control of DC Servomotor
...Show More Authors

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.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Dec 15 2021
Journal Name
Al-academy
Shorthand and Implicit in Graphic Design
...Show More Authors

 Reduction represents a form of artistic abstraction to express things with formal symbols that suggest the content of the idea, as the beauty of the design artwork cannot be unique in the form only, but in revealing its meaning as well. He resorts to shorthand to express the content of his idea related to design necessities and needs to achieve a specific function whose role is crystallized through the form that follows the function. The importance of the research was also represented in: Benefiting workers and scholars in the field of design with regard to shorthand and implicit in graphic design. The aim of the research: to identify the relationship between implicit meaning and reduced forms in graphic design. And the aesthetic of fo

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun May 02 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Value at risk simulation in a fixed return stock portfolio using the Monte Carlo simulation model The concept of a bond portfolio
...Show More Authors

This research aims to predict the value of the maximum daily loss that the fixed-return securities portfolio may suffer in Qatar National Bank - Syria, and for this purpose data were collected for risk factors that affect the value of the portfolio represented by the time structure of interest rates in the United States of America over the extended period Between 2017 and 2018, in addition to data related to the composition of the bonds portfolio of Qatar National Bank of Syria in 2017, And then employing Monte Carlo simulation models to predict the maximum loss that may be exposed to this portfolio in the future. The results of the Monte Carlo simulation showed the possibility of decreasing the value at risk in the future due to the dec

... Show More
View Publication Preview PDF
Publication Date
Tue Mar 01 2016
Journal Name
Al-academy
The aesthetics of design shape of the interior spaces for the syndicate of physicians: ريم باسل نوري
...Show More Authors

The research dealt with the topic ' the aesthetics of design shape of interior spaces for the syndicate of physicians' as it reflects visions evolving to the level of tasting and positive interpretation for the space of work to be on a high design level.The research consisting of four chapters as follow; The first chapter examined the problem of the research contracted in the following question: Have the design shapes any role in achieving and showing the aesthetic side for the syndicate of physicians? so the goal of the research was showing the aesthetics of design shape of interior spaces for the syndicate of physicians, The chapter also included the objective spatial and temporal limits of research .Finally the terms were specified. T

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Mar 27 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Design, Synthesis and Preliminary Antimicrobial Evaluation of New Derivatives of Cephalexin
...Show More Authors

There is a continuous and massive need for newer cephalosporins that should have resistance against β-lactamases and can be used orally. An approach of using cephalexin, as a well-studied and potent antibacterial compound is considered to prepare new designed derivatives.  These derivatives include the incorporation of amino acid moiety linked through an amide bond with the α-amino group of cephalexin. Certain aliphatic amino acids were used, such as glycine, alanine, valine and proline. The chemical structures of these derivatives were confirmed by IR spectroscopy and elemental analyses. All the synthesized compounds were subjected for preliminary evaluation of antimicrobial activity using well diffusion method, against certa

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Jun 23 2022
Journal Name
American Scientific Research Journal For Engineering, Technology, And Sciences
A Review of TCP Congestion Control Using Artificial Intelligence in 4G and 5G Networks
...Show More Authors

In recent years, the field of research around the congestion problem of 4G and 5G networks has grown, especially those based on artificial intelligence (AI). Although 4G with LTE is seen as a mature technology, there is a continuous improvement in the infrastructure that led to the emergence of 5G networks. As a result of the large services provided in industries, Internet of Things (IoT) applications and smart cities, which have a large amount of exchanged data, a large number of connected devices per area, and high data rates, have brought their own problems and challenges, especially the problem of congestion. In this context, artificial intelligence (AI) models can be considered as one of the main techniques that can be used to solve ne

... Show More
View Publication
Publication Date
Thu Jun 26 2025
Journal Name
Journal Of Baghdad College Of Dentistry
The influence of shifting the class I cavity position prepared in posterior teeth buccally and lingualy on stress distribution (Finite element analysis study)
...Show More Authors

Background: Rehabilitation of the carious tooth to establish tooth structure integrity required cavity design that show a benign stress distribution. The aim of this study was to investigate the influence of the cavity position on the stress values in the reamining tooth structure restored with amalgam or resin composite. Materials and methods: Seven 2-D models of maxillary first premolar include class I cavity design was prepared, one sound tooth (A) 3 composite (B1, B2, and B3) and 3 amalgam (C1, C2, and C3). In design (BI and C1) the cavity position is in the mid distance between bacc-lingual cusp tip, design (B2 and C2) and (B3 and C3) shifted toward the buccal cusp and the lingual cusp for 0.5 mm respectively. One hundred N vertical

... Show More
View Publication Preview PDF
Publication Date
Tue Dec 01 2015
Journal Name
Journal Of Engineering
Aeroelastic Flutter of Subsonic Aircraft Wing Section with Control Surface
...Show More Authors

Aeroelastic flutter in aircraft mechanisms is unavoidable, essentially in the wing and control surface. In this work a three degree-of-freedom aeroelastic wing section with trailing edge flap is modeled numerically and theoretically. FLUENT code based on the steady finite volume is used for the prediction of the steady aerodynamic characteristics (lift, drag, pitching moment, velocity, and pressure distribution) as well as the Duhamel formulation is used to model the aerodynamic loads theoretically. The system response (pitch, flap pitch and plunge) was determined by integration the governing equations using MATLAB with a standard Runge–Kutta algorithm in conjunction with Henon’s method. The results are compared with

... Show More
View Publication Preview PDF
Publication Date
Sun Sep 01 2019
Journal Name
Al-khwarizmi Engineering Journal
The Effect of Wind Velocity on the Suppression of Composite Wing Airfoil NACA 0012
...Show More Authors

The first studies on shocks and vibrations were carried out at the beginning of the 1930s to improve the behavior of buildings during earthquakes. Vibration tests on aircraft were developed from 1940 to verify the resistance of parts and equipments prior to their first use. Flutter is a well-known example of dynamic aero elasticity, where when oscillation of structure interacted with unsteady aerodynamic forces the flutter will occur. Vibration on any structure without damping means that self-harmonic oscillation will occur, and in most cases the oscillation may start to increase until structural failure. This behavior is very similar to resonance phenomena if only the oscillation is being studied as a vibration case. In vibration suppre

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Wed Mar 23 2022
Journal Name
Journal Of Educational And Psychological Researches
Mental wandering and its relationship to attention control among university students
...Show More Authors

Research summary: The current research aims to identify:

1-Mental wandering among university students 2- Attentioncontrol among universitey students. 3- The relationship between mental wandering and attention control among university students. 4- The difference in the relationship among university students: accoerding to a- the gender variable (males - females) b- according to the specialization variable) Scientific-human), and the results of the current research reached the following: 1- University students have mental wandering associated with the task, and mental wandering that is not related to the task. 2- University students have attentive control 3- There is no relationship between mental wandering associated with task and

... Show More
View Publication Preview PDF
Publication Date
Sun Oct 01 2023
Journal Name
Int. J. Nonlinear Anal. Appl
Adaptive 1-D polynomial coding to compress color image with C421
...Show More Authors