Preferred Language
Articles
/
joe-1297
Assessment of the Cost and Time Impact of Variation Orders on Construction Projects in Sulaimani Governorate
...Show More Authors

Variation orders are an on-going phenomenon in construction and industry projects worldwide, particularly in the province of Sulaimani, where the project's damage from cost and schedule overrun because of variation orders. However, the effect on project costs and time overrun of variation order has yet to be identified. This study evaluates the impact of variation orders on the cost and time off in the Sulaimani governorate. Two hundred twenty-eight projects from various construction sectors built between 2007-2012 were adopted to calculate the contract cost and schedule overruns due to variation orders. Data analysis was applied in the study were descriptive statistics. One-way ANOVA was also applied to determine whether the overrun of project cost and schedule significantly varied depending on project type, size, duration, location, and awarded years. The findings indicated that cost overruns are very common due to variation orders. 95.6% of the projects were studied being impacted, and overrun in project cost are also huge, with 16%. Time also overruns more common than cost overruns due to the variation orders. 98.7% of the projects were studied in Sulaimani were affected by time overrun with an average of 46.3% of initial duration observed. Findings also indicated that two out of five parameters measured in the analysis had a significant correlation with project cost overruns. Three out of five considered variables correlated with construction time overruns. 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Sep 02 2022
Journal Name
Rawal Medical Journal
Comminuted intra-articular distal radius fractures treated by ligamentotaxis external fixation with and without bone marrow injection to prevent late metaphyseal collapse
...Show More Authors

Objective: To compare the radiological and functional outcomes of patients of Comminuted intraarticular distal radius fractures treated with or without bone marrow injection along with external fixator ligamentotaxis. Methodology: This prospective comparative study on 41 patients with comminuted intra-articular lower end radius fractures distributed patients randomly into two groups depending on whether an aspirate of bone marrow was injected at the fracture site two weeks after fracture management with external fixation ligamentotaxis. Results: The mean age was 35.8 years, with male predominance. The radiological parameters (radial height, radial inclination, and volar tilt) at the 6th month follow up were lower in the group who did not re

... Show More
Preview PDF
Scopus
Publication Date
Wed Aug 01 2018
Journal Name
Collegian
Behaviour change interventions to improve medication adherence in patients with cardiac disease: Protocol for a mixed methods study including a pilot randomised controlled trial
...Show More Authors

View Publication
Scopus (9)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Fri Mar 31 2017
Journal Name
Al-khwarizmi Engineering Journal
Preparation of Light Fuel Fractions from Heavy Vacuum Gas Oil by Thermal Cracking Reaction
...Show More Authors

This work deals with thermal cracking of heavy vacuum gas oil which produced from the top of vacuum distillation unit at Al- DURA refinery, by continuous process. An experimental laboratory plant scale was constructed in laboratories of chemical engineering department, Al-Nahrain University and Baghdad University. The thermal cracking process was carried out at temperature ranges between 460-560oC and atmospheric pressure with liquid hourly space velocity (LHSV) equal to 15hr-1.The liquid product from thermal cracking unit was distilled by atmospheric distillation device according to ASTM D-86 in order to achieve two fractions, below 220oC as a gasoline fraction and above 220oC as light cycle o

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Performance Comparison of Different Advanced Control Schemes for Glucose Level Control under Disturbing Meal
...Show More Authors

Abstract

In this work, diabetic glucose concentration level control under disturbing meal has been controlled using two set of advanced controllers. The first set is sliding mode controllers (classical and integral) and the second set is represented by optimal LQR controllers (classical and Min-, ax). Due to their characteristic features of disturbance rejection, both integral sliding mode controller and LQR Minmax controller are dedicated here for comparison. The Bergman minimal mathematical model was used to represent the dynamic behavior of a diabetic patient’s blood glucose concentration to the insulin injection. Simulations based on Matlab/Simulink, were performed to verify the performance of each controll

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Mar 01 2016
Journal Name
Journal Of Engineering
Some Mechanical Properties of Concrete by using Manufactured Blended Cement with Grinded Local Rocks
...Show More Authors

The  use  of  blended  cement  in  concrete  provides economic, energy savings,  and ecological  benefits, and also  provides. Improvement in the properties of materials incorporating blended cements. The  major  aim  of  this  investigation  is  to  develop  blended  cement  technology using  grinded local rocks . The research includes information on constituent materials, manufacturing processes and performance characteristics of blended cements made with replacement (10 and 20) % of grinded local rocks (limestone, quartzite and porcelinite) from cement.

The main conclusion of this study was that all ty

... Show More
View Publication Preview PDF
Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
SIMULATION OF OPTIMAL SPEED CONTROL FOR A DC MOTOR USING LINEAR QUADRATIC REGULATOR (LQR)
...Show More Authors


This paper describes DC motor speed control based on optimal Linear Quadratic Regulator (LQR) technique. Controller's objective is to maintain the speed of rotation of the motor shaft with a particular step response.The controller is modeled in MATLAB environment, the simulation results show that the proposed controller gives better performance and less settling time when compared with the traditional PID controller.

View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Sun Jun 01 2025
Journal Name
Journal Of Physics: Conference Series
Searching Ground State Properties of some Light Proton-Rich Nuclei Using Whittaker Wave Functions
...Show More Authors
Abstract<p>In this work, the Whittaker wave functions were used to study the nuclear density distributions and elastic electron scattering charge form factors for proton-rich nuclei and their corresponding stable nuclei (<sup>10,8</sup>B, <sup>13,9</sup>C, <sup>14,12</sup>N and <sup>19,17</sup>F). The parameters of Whittaker’s basis were fixed to generate the experimental values of available size radii. The Whittaker basis was connected to harmonic-oscillator basis through boundary condition at match point. The nuclear shell model was opted with pure configuration for all studied nuclei to compute aforementioned studied quantities except <sup>10</sup></p> ... Show More
View Publication
Scopus Crossref
Publication Date
Sun Jun 20 2021
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
FIRST RECORD OF OPILIO KAKUNINI SNEGOVAYA, COKENDOLPHER & MOZAFFARIAN, 2018 (ARACHNIDA, OPILIONES, PHALANGIIDAE) FROM IRAQ
...Show More Authors

The species of Opilio kakunini Snegovaya, Cokendolpher & Mozaffarian, 2018 was recorded for the first time in Iraq; as well as to four species belonging to this order which were recorded previously. In this paper, we added a new species to the checklist of Iraqi opilionid fauna with a description of the most important characteristics, along with genitalia, for both males and females are presented with digital photographs. Specimens of males and females were collected from Al- Rifai district northern of Dhi-Qar Province, southern of Iraq.
 

View Publication Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Wed Jul 31 2019
Journal Name
Journal Of Engineering
Buckling Analysis of Laminated Composite Plate with Different Boundary Conditions using modified Fourier series
...Show More Authors

Buckling analysis of a laminated composite thin plate with different boundary conditions subjected to in-plane uniform load are studied depending on classical laminated plate theory; analytically using (Rayleigh-Ritz method). Equation of motion of the plates was derived using the principle of virtual work and solved using modified Fourier displacement function that satisfies general edge conditions. The eigenvalue problem generated by using Ritz method, the set of linear algebraic equations can be solved using MATLAB for symmetric and anti-symmetric, cross and angle-ply laminated plate considering some design parameters such as aspect ratios, number of layers, lamination type and orthotropic ratio. The results obtained g

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Thu Dec 14 2023
Journal Name
Iete Journal Of Research
Performance Enhancement of VLC-NOMA Employing Beamforming Function based vehicle-to-multivehicle Communication system
...Show More Authors

View Publication
Scopus (4)
Crossref (2)
Scopus Clarivate Crossref