Preferred Language
Articles
/
DxcPZpIBVTCNdQwCjq-R
Finite Time Disturbance Observer Based on Air Conditioning System Control Scheme
...Show More Authors

A novel robust finite time disturbance observer (RFTDO) based on an independent output-finite time composite control (FTCC) scheme is proposed for an air conditioning-system temperature and humidity regulation. The variable air volume (VAV) of the system is represented by two first-order mathematical models for the temperature and humidity dynamics. In the temperature loop dynamics, a RFTDO temperature (RFTDO-T) and an FTCC temperature (FTCC-T) are designed to estimate and reject the lumped disturbances of the temperature subsystem. In the humidity loop, a robust output of the FTCC humidity (FTCC-H) and RFTDO humidity (RFTDO-H) are also designed to estimate and reject the lumped disturbances of the humidity subsystem. Based on Lyapunov theory, the stability proof of the two closed-loop controllers and observers is presented. Comparative simulations are carried out to confirm that the proposed controller outperforms conventional methods and offers greater accuracy of temperature, humidity, and carbon dioxide concentration, having superior regulation performance in terms of a rapid finite time convergence, an outstanding disturbance rejection property, and better energy consumption. In addition to presenting the comparative simulation results from the control applications on the VAV system, the quantitative values are provided to further confirm the superiority of the proposed controller. In particular, the proposed method exhibits the shortest settling time of, respectively, 15 and 40 min to reach the expected temperature and humidity, whereas other comparative controllers require a longer time to settle down.

Scopus Clarivate Crossref
View Publication
Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Engineering
A Realistic Aggregate Load Representation for A Distribution Substation in Baghdad Network
...Show More Authors

Electrical distribution system loads are permanently not fixed and alter in value and nature with time. Therefore, accurate consumer load data and models are required for performing system planning, system operation, and analysis studies. Moreover, realistic consumer load data are vital for load management, services, and billing purposes. In this work, a realistic aggregate electric load model is developed and proposed for a sample operative substation in Baghdad distribution network. The model involves aggregation of hundreds of thousands of individual components devices such as motors, appliances, and lighting fixtures. Sana’a substation in Al-kadhimiya area supplies mainly residential grade loads. Measurement-based

... Show More
View Publication Preview PDF
Publication Date
Sat Nov 04 2023
Journal Name
Migration Letters
The Concept of Reform According to the Quranic Perspective
...Show More Authors

This research is an initial attempt to explore the reality of reform and its concept in Islam, and to describe the presence of educational practices in the Arab-Islamic heritage. The importance of this research lies in addressing a number of important issues related to the contemporary Islamic reform system. The research showed the need for authentic educational reform values that draw their reference from the origins of Islam. The research also emphasized the analysis of the reality of education in the Muslim world and the identification of its problems and the search for solutions through a quick and comprehensive look at the diverse contributions of Muslim thinkers to Islamic educational reform thought, and their active role in addressin

... Show More
Publication Date
Fri Dec 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
The application of quality requirements in the Ministry of Labour and Social Affairs using the international standard (ISO 9001: 2015) Korean case study of the Iraqi Center
...Show More Authors

This research aims to study the mechanism of application of international specification requirements (ISO 9001: 2015) at the Iraqi Center- Korean Vocational Training return to vocational training department at the Ministry of Labour and Social Affairs for the purpose of preparing and creating the center to get a certificate of conformity with the requirements of the standard (ISO 9001: 2015) that would elevate the level of performance and services provided in the respondent Center after it is identified and the study of the reality of the quality management system by identifying strengths and weaknesses in the system to diagnose the gap and find ways to address that gap, and adopted the researchers the case study method to conduc

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Jun 30 2019
Journal Name
Journal Of Engineering
Thermal Performance of Plastic Receiver in Solar Collector
...Show More Authors

A plastic tubes used as absorber of active flat plate solar collector (FPSC) for heating water were studied numerically and experimentally. The set-up is located in Babylon (republic of Iraq) 43.80 East longitude and 32.30 North latitude with titled of 450 toward the south direction.  The study involved three dimensions mathematical model for flat coil plastic absorber which solved by FLUENT-ANSYS-R.18 program. Experiments were conducted at outdoor conditions for clear days on January and February 2018 with various water volume flow rates namely (500, 750, 1000, 1250, and 1500 Liter per hour LPH) on each month for Reynolds number range of (1 x 104 to 5 x 104) th

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sun Jul 11 2021
Journal Name
Sustainable Civil Infrastructures
Field Soil Electrical Resistivity Measurements of Some Soil of Iraq
...Show More Authors

View Publication
Scopus (2)
Crossref (1)
Scopus Crossref
Publication Date
Mon Feb 04 2019
Journal Name
Iraqi Journal Of Physics
Estimation of electron temperature for SiO2 plasma induced by laser
...Show More Authors

In this work; Silicon dioxide (SiO2) were fabricated by pulsed
laser ablation (PLA). The electron temperature was calculated by
reading the data of I-V curve of Langmuir probe which was
employed as a diagnostic technique for measuring plasma properties.
Pulsed Nd:YA Glaser was used for measuring the electron
temperature of SiO2 plasma plume under vacuum environment with
varying both pressure and axial distance from the target surface. The
electron temperature has been measured experimentally and the
effects of each of pressure and Langmuir probe distance from the
target were studied. An inverse relationship between electron
temperature and both pressure and axial distance was observed.

View Publication Preview PDF
Crossref
Publication Date
Thu Nov 21 2019
Journal Name
Journal Of Engineering
Thermal Buckling of Angle-Ply Laminated Plates Using New Displacement Function
...Show More Authors

ABSTRACT

Critical buckling temperature of angle-ply laminated plate is developed using a higher-order displacement field. This displacement field used by Mantari et al based on a constant ‘‘m’’, which is determined to give results closest to the three dimensions elasticity (3-D) theory. Equations of motion based on higher-order theory angle ply plates are derived through Hamilton, s principle, and solved using Navier-type solution to obtain critical buckling temperature for simply supported laminated plates. Changing (α2/ α1) ratios, number of layers, aspect ratios, E1/E2 ratios for thick and thin plates and their effect on thermal

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Sat Oct 01 2022
Journal Name
Baghdad Science Journal
Using Remote Sensing and Geographic Information Systems to Study the Change Detection in Temperature and Surface Area of Hamrin Lake
...Show More Authors

This study was conducted on Lake Hamrin situated in Diyala governorate, focal Iraq, between latitudes 44º 53ʹ 26.16 '- 45º 07 ʹ 28.03ʺ and 34º 04ʹ 24.75ʺ ــ 34º 19ʹ 12.74ʺ . As in this study, the surface area of Hamrin Lake was calculated from satellite images during the period from October 2019 to September 2020, with an average satellite image for each month, furthermore,by utilizing the Normalized Differences Water Index (NDWI), the largest surface area was 264,617 km2 for October and the lowest surface area 140.202 km2 for September. The surface temperature of the lake water was also calculated from satellite images of the Landsat 8 satellite, based on ban

... Show More
View Publication Preview PDF
Scopus (4)
Scopus Clarivate Crossref
Publication Date
Sun Jul 30 2023
Journal Name
Iraqi Journal Of Science
Estimation of the Standard Atmospheric Earth Model Parameters at 86 km Altitude
...Show More Authors

     Utilizing the Turbo C programming language, the atmospheric earth model is created from sea level to 86 km. This model has been used to determine atmospheric Earth parameters in this study. Analytical derivations of these parameters are made using the balancing forces theory and the hydrostatic equation. The effects of altitude on density, pressure, temperature, gravitational acceleration, sound speed, scale height, and molecular weight are examined. The mass of the atmosphere is equal to about 50% between sea level and 5.5 km. g is equal to 9.65 m/s2 at 50 km altitude, which is 9% lower than 9.8 m/s2 at sea level. However, at 86 km altitude, g is close to 9.51 m/s2, which is close to 15% smaller than 9.8 m/s2.  These resu

... Show More
Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Sat Dec 01 2012
Journal Name
International Journal Of Contemporary Mathematical Sciences
Approximation by Convex Polynomials in Weighted Spaces
...Show More Authors

Here, we found an estimation of best approximation of unbounded functions which satisfied weighted Lipschitz condition with respect to convex polynomial by means of weighted Totik-Ditzian modulus of continuity