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
Wed Mar 01 2017
Journal Name
Journal Of Al-nahrain University Science
Adsorption of Ciprofloxacin Hydrochloride from Aqueous Solution by Iraqi Porcelinaite Adsorbent
...Show More Authors

View Publication
Crossref (7)
Crossref
Publication Date
Sat Aug 01 2020
Journal Name
Key Engineering Materials
Systematic Design of Short-Span Segmental Beams Reinforced by CFRP Plates
...Show More Authors

The main objective of this study is to introduce a systematic design procedure for short-span segmental beams following a sophisticated ACI 440.2R-17 design procedure. The general aspects of innovative short-span segmental beams are easy to fabricate, economical and rapidly placed in pre-specified positions. Short-span segmental beams fabricated from individual precast plain-concrete blocks and CFRP plates. Recently, experimental tests performed on short-span segmental beams, by the authors, investigated CFRP plate-bonding, CFRP plate cross-sectional area, the thickness of plate-bonding epoxy resin, surface-to-surface condition of concrete blocks, as well as, interface condition of the bonding surface. The experimental program comprises tes

... Show More
View Publication
Scopus (5)
Crossref (5)
Scopus Crossref
Publication Date
Sat Aug 01 2020
Journal Name
Key Engineering Materials
Response of Damaged Reinforced Concrete Beams Strengthened with NSM CFRP Strips
...Show More Authors

This paper presents a study (experimentally) for strengthening reinforced concrete (RC) beams with Near-Surface-Mounted (NSM) technique. The use of this technique with CFRP strips or rebars is an efficient technology for increasing the strength for flexure and shear or for repairing damaged reinforced concrete (RC) members. The objective of this research is to study, experimentally, RC beams either repaired or strengthened with NSM CFRP strips and follow their flexural behavior and failure modes. NSM-CFRP strips were used to strengthen three RC beam specimens, one of them was initially strengthened and tested up to failure. Four beam specimens have been initially subjected to preloading to 50% and 80% of ultimate load. Two of the sp

... Show More
View Publication
Crossref (1)
Crossref
Publication Date
Thu Oct 01 2015
Journal Name
Iraqi Journal Of Science
optimization of pectinase production from pesudomonas sp. isolated from iraqi soi
...Show More Authors

Publication Date
Sun Jun 04 2017
Journal Name
Baghdad Science Journal
Synthesis of Pure Nano semiconductor Oxide ZnO with Different AgNO3 Concentrations
...Show More Authors

Zinc oxide nanoparticles sample is prepared by the precipitation method. This method involves using zinc nitrate and urea in aqueous solution, then (AgNO3) Solution with different concentrations is added. The obtained precipitated compound is structurally characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). The average particle size of nanoparticles is around 28nm in pure, the average particle size reaches 26nm with adding AgNO3 (0.05g in100ml =0.002 M) (0.1g in100ml=0.0058M), AgNO3 (0.2g in 100ml=0.01M) was 25nm. The FTIR result shows the existence of -CO, -CO2, -OH, and -NO2- groups in sample and oxides (ZnO, Ag2O).and used an

... Show More
View Publication Preview PDF
Scopus (4)
Scopus Crossref
Publication Date
Wed Sep 30 2020
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Production of 7-methylxanthine from Theobromine by Metabolically Engineered E. coli
...Show More Authors

In this work, a novel biocatalytic process for the production of 7-methylxanthines from theobromine, an economic feedstock has been developed. Bench scale production of 7-methlxanthine has been demonstrated. The biocatalytic process used in this work operates at 30 OC and atmospheric pressure, and is environmentally friendly. The biocatalyst was E. coli BL21(DE3) engineered with ndmB/D genes combinations. These modifications enabled specific N7- demethylation of theobromine to 7-methylxanthine. This production process consists of uniform fermentation conditions with a specific metabolically engineered strain, uniform induction of specific enzymes for 7-methylxanthine production, uniform recovery an

... Show More
View Publication Preview PDF
Crossref (9)
Crossref
Publication Date
Sat Jun 26 2021
Journal Name
Journal Of Engineering
Adsorption Desulfurization of Iraqi Light Naphtha Using Metals Modified Activated Carbon
...Show More Authors

The study aims to evaluate the removal of sulfur content from Iraqi light naphtha produced in Al-Dora refinery by adsorption desulfurization DS technique using modified activated carbon MAC loaded with nickel Ni and copper Cu as single binary metals. The experiments were carried in a batch unit with various operating parameters;  MAC dosage, agitation speed, and a contact time of 300 min at constant initial sulfur concentration 155 ppm and temperature. The results showed higher DS% by AC/Ni-Cu (66.45)% at 500 rpm and 1 g dosage than DS (29.03)% by activated carbon AC, increasing MAC dosage, agitation speed, and contact time led to increasing DS% values.  The adsorption capacity of MAC results was recorded (16, 15, and 20) mg sulfu

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Dec 31 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Removal of Heavy Metals from Industrial Wastewater by Using RO Membrane
...Show More Authors

Industrial wastewater containing nickel, lead, and copper can be produced by many industries. The reverse osmosis (RO) membrane technologies are very efficient for the treatment of industrial wastewater containing nickel, lead, and copper ions to reduce water consumption and preserving the environment. Synthetic industrial wastewater samples containing Ni(II), Pb(II), and Cu(II) ions at various concentrations (50 to 200 ppm), pressures (1 to 4 bar), temperatures (10 to 40 oC), pH (2 to 5.5), and flow rates (10 to 40 L/hr), were prepared and subjected to treatment by RO system in the laboratory. The results showed that high removal efficiency of the heavy metals could be achieved by RO process (98.5%, 97.5% and 96% for Ni(II),

... Show More
View Publication Preview PDF
Publication Date
Sun Sep 01 2024
Journal Name
Rafidain Journal Of Science
Therapeutic Potential of Bacterial Pigments as Antimicrobial Agents A Review Article
...Show More Authors

View Publication Preview PDF
Crossref
Publication Date
Thu Aug 05 2021
Journal Name
International Journal Of Renewable Energy Development
Desalination of Agricultural Wastewater by Solar Adsorption System: A Numerical Study
...Show More Authors

There are still areas around the world suffer from severe shortage of freshwater supplies. Desalination technologies are not widely used due to their high energy usage, cost, and environmental damaging effects. In this study, a mathematical model of single-bed adsorption desalination system using silica gel-water as working pair is developed and validated via earlier experiments. A very good match between the model predictions and the experimental results is recorded. The objective is to reveal the factors affecting the productivity of fresh water and cooling effect in the solar adsorption system. The proposed model is setup for solving within the commercially-available software (Engineering Equation Solver). It is implemented to so

... Show More
View Publication
Scopus (8)
Crossref (6)
Scopus Clarivate Crossref