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Assessment of the Cost and Time Impact of Variation Orders on Construction Projects in Sulaimani Governorate
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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. 

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Publication Date
Mon Jan 01 2018
Journal Name
Journal Of Physics Conference Series
Enhanced phot-respons of porous silicon photo- detectors by embedding Titanium -dioxide nano-particles
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: Porous silicon (n-PS) films can be prepared by photoelectochemical etching (PECE) Silicon chips n - types with 15 (mA /cm2), in15 minutes etching time on the fabrication nano-sized pore arrangement. By using X-ray diffraction measurement and atomic power microscopy characteristics (AFM), PS was investigated. It was also evaluated the crystallites size from (XRD) for the PS nanoscale. The atomic force microscopy confirmed the nano-metric size chemical fictionalization through the electrochemical etching that was shown on the PS surface chemical composition. The atomic power microscopy checks showed the roughness of the silicon surface. It is also notified (TiO2) preparation nano-particles that were prepared by pulse laser eradication in e

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Publication Date
Tue May 01 2018
Journal Name
Journal Of Physics: Conference Series
Synthesis of ZnS Quantum Dots for QDs-LED hybrid device with different cathode materials
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Publication Date
Mon Aug 04 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Force decay of orthodontic elastomeric chains by using three different mechanisms simulating canine retraction
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Background: The ideal force-delivery system must: provide optimal tooth moving forces that elicit the desired effects, be comfortable and hygienic for the patient, require minimal operator manipulation and patient cooperation and provide rapid tooth movement with minimal mobility during orthodontic therapy, the elastomeric chains have the greatest potential to fulfill these requirements. Materials and Methods: This in vitro study was designed to determine the effect of three different mechanisms for canine retraction : (6-3 , 6-5-3 and chain loop ) on the load relaxation behavior of three types of elastomeric chains : (maximum clear , maximum silver and extreme silver) from the same company (Ortho Technology company) with two different bran

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Publication Date
Mon Oct 02 2023
Journal Name
Journal Of Polymer Research
Morphological study of porous aromatic schiff bases as a highly effective carbon dioxide storages
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Carbon dioxide (CO2) capture and storage is a critical issue for mitigating climate change. Porous aromatic Schiff base complexes have emerged as a promising class of materials for CO2 capture due to their high surface area, porosity, and stability. In this study, we investigate the potential of Schiff base complexes as an effective media for CO2 storage. We review the synthesis and characterization of porous aromatic Schiff bases materials complexes and examine their CO2 sorption properties. We find that Schiff base complexes exhibit high CO2 adsorption capacity and selectivity, making them a promising candidate for use in carbon capture applications. Moreover, we investigate the effect of various parameters such as temperature, and pressu

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Publication Date
Thu Sep 13 2018
Journal Name
Baghdad Science Journal
Estimation of some Organophosphorus Pesticides Using Carbon Paste Electrode Coupled with Molecularly Imprinted Polymers
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The aim of this study was to develop a sensor based on a carbon paste electrodes (CPEs) modified with used MIP for determination of organophosphorus pesticides (OPPs). The modified electrode exhibited a significantly increased sensitivity and selectivity of (OPPs). The MIP was prepared by thermo-polymerization method using N,N-diethylaminoethymethacrylate (NNDAA) as functional monomer, N,N-1,4-phenylenediacrylamide (NNPDA) as cross-linker, the acetonitrile used as solvent and (Opps) as the template molecule. The three OPPs (diazinon, quinalphos and chlorpyrifos) were chosen as the templates, which have been selected as base analytes which used widely in agriculture sector. The extraction efficiency of the imprinted polymers has been evaluat

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Publication Date
Tue Dec 01 2015
Journal Name
Second Engineering Scientific Conference
SEPARATION OF ALKALOIDS FROM PLANTS BY BULK LIQUID MEMBRANE TECHNIQUE USING ROTATING DISCS CONTACTOR
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This paper describes the transport of Alkaloids through Rotating Discs Contactor (RDC) using n-decane as a liquid membrane. The transport of Pelletierine Alkaloid from a source phase through bulk liquid membrane to the receiving phase has been investigated. The general behaviour of Pertraction process indicates that% Extraction of pelletierine Alkaloid increased with increase in the number of stages and the agitation speed but high agitation speed was not favoured due to the increased risk of droplet formation during the operation. The pH of source and receiving phases were also investigated. The effect of organic solvent membrane on the extraction of Pelletierine was evaluated using ndecane, n-hexane and methyl cyclohexane. The results sho

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Publication Date
Sat Mar 01 2025
Journal Name
Journal Of Ecological Engineering
Synthesis of sulfated zirconia-HY zeolite catalysts doped by platinum metal for hydroisomerization reaction
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Publication Date
Sun Jan 01 2023
Journal Name
8th Engineering And 2nd International Conference For College Of Engineering – University Of Baghdad: Coec8-2021 Proceedings
Serviceability performance of high-strength concrete flexural members with internally unbonded post-tensioning strands
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Publication Date
Wed Jan 01 2020
Journal Name
Plant Archive
Isolation of candida spp. From cancer patients who suffered oral candidiasis due to immunodeficiency
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solation of candida spp. From cancer patients who suffered oral candidiasis due to immunodeficiency

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Publication Date
Sat Feb 01 2020
Journal Name
International Journal Of Electrical And Computer Engineering (ijece)
PSS/E based placement wind/PV hybrid system to improve stability of Iraqi grid
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<span lang="EN-US">Proper employment of Hybrid Wind/ PV system is often implemented near the load, and it is linked with the grid to study dynamic stability analysis. Generally, instability is because of sudden load demand variant and variant in renewable sources generation. As well as, weather variation creates several factors that affect the operation of the integrated hybrid system. So this paper introduces output result of a PV /wind via power electronic technique; DC chopper; that is linked to Iraqi power system to promote the facilitating achievement of Wind/ PV voltage. Moreover, PSS/E is used to study dynamic power stability for hybrid system which is attached to an effective region of Iraqi Network. The hybrid system

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