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Developing a Risk Assessment Model Based on Time Value of Money and Cost-Benefit Ratio in Construction Projects
Roghaye Mousazade,
Abbas Mahmoudabadi
Issue:
Volume 2, Issue 2, April 2017
Pages:
34-43
Received:
24 January 2017
Accepted:
20 February 2017
Published:
3 March 2017
DOI:
10.11648/j.jccee.20170202.11
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Abstract: In the present paper, a cost-risk and income-risk evaluation model has been developed in order to evaluate the risks of cost and incomes those may happen in construction projects. Since, it is important to determine risk factors for different activities and stages of various projects; the main aim is to propose an evaluation model for estimating the present value of risks corresponding to costs and incomes of the construction projects. The estimating procedure which has been proposed in this research work is that a project is broken into stages and related activities and the present value of cost and income risks as well as the value of different risk groups are calculated and compared to three pre-defined risk categories. Utilizing the proposed procedure using experimental data gathering for a under construction primary school building shows that the proposed model can help decision makers to determine and assess the risks of cost and incomes over the project activities. In addition, using the proposed procedure helps them to talk about how to deal with those risks to be reduced, accepted or transferred to other project components.
Abstract: In the present paper, a cost-risk and income-risk evaluation model has been developed in order to evaluate the risks of cost and incomes those may happen in construction projects. Since, it is important to determine risk factors for different activities and stages of various projects; the main aim is to propose an evaluation model for estimating th...
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Use of Shallow Groundwater in Sprinkler Irrigation (Case Study)
Aqeel Al-Adili,
Mohammed R. Mohammed,
Haider H. Alwash
Issue:
Volume 2, Issue 2, April 2017
Pages:
44-58
Received:
2 December 2016
Accepted:
1 March 2017
Published:
24 March 2017
DOI:
10.11648/j.jccee.20170202.12
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Abstract: The study area is located in the desert region west of the road to Karbala-Najaf cities. The unconfined Al-Dibdibba aquifer in this area is considered as a source of water. Recently, the project of the city of Al-Imam Al-Hussein farm has been established in this area which depends on the groundwater for irrigation. The general direction of ground water in the aquifer is from the west and the south west towards the east and the northeast. The storage of the aquifer is about 46.8 Million m3. Two different sites were selected; the first site is the front field which includes 4 wells, while the second site is the back field which includes 20 wells. Basins have been suggested to be constructed with a volume of 3000 m3 for each one of farms A and B in the back field and a volume of 1500 m3 for farm C in the front field. The results of electrical conductivity-EC of ground water-GW samples indicate that are suitable for wheat, barley, maize, and sugar beet. Simulation models have been used at two phases in this research with an area of 51 donums for the back field and 33 donums for farm C in the front field. The first phase is to find crop water requirement and irrigation requirements for wheat and barley as a winter crops and maize and sugarbeet as a summer crops using CROPWAT8.0 simulation model, while the second phase includes irrigation network design using EPANET2.0 simulation model. This study has revealed that the final designed semi-permanent sprinkler system capacity in this research is 321m3/hr to irrigate area of 51 donum, within 4 days of 7 hours per day for the back field. Thus, the application of sprinkler irrigation will assist in the increase of cultivation by about 2.5 times. Also, results from simulation showed that the operation time of wells has been reduced about 40%. Crop yield produced by donum for each crop was increased by about 50%.
Abstract: The study area is located in the desert region west of the road to Karbala-Najaf cities. The unconfined Al-Dibdibba aquifer in this area is considered as a source of water. Recently, the project of the city of Al-Imam Al-Hussein farm has been established in this area which depends on the groundwater for irrigation. The general direction of ground w...
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Electrical Resistivity and River Flow Velocity Studies of Ebonyi River Bridge Sites at Onicha-Oshiri and Idembia Areas, Southeastern Nigeria
Ibeneme Sabinus Ikechukwu,
Ibe Kalu Kalu,
Eluwa Ndidiamaka Nchedo,
Chinyem Felix Iwebunor,
Nwankwo Stephen,
Bulus Joseph Azi,
Echendu Obi Kingsley
Issue:
Volume 2, Issue 2, April 2017
Pages:
59-65
Received:
4 March 2017
Accepted:
16 March 2017
Published:
30 March 2017
DOI:
10.11648/j.jccee.20170202.13
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Abstract: Pre-design Geoelectrical and River Velocity studies have been carried out at two bridge locations: Ebonyi River at Onicha-Oshiri road and Ebonyi River at Idembia Ezza. The objectives of the studies are to determine the geoelectrical parameters with respect to structure and rock type at these locations in combination with geology and carry out the analysis of the river velocity at various points. Four Vertical Electrical Sounding (VES) stations and six Velocity profiles were established (two VES stations and three velocity profiles per bridge site). Three geoelectric layers were proposed for Onicha-Oshiri and four to five geoelectric layers for Idembia. These layers comprise of the Top soil with resistivity range of 290-950Ωm, Silty lateritic soil with resistivity range of 140-181Ωm, Hard lateritic soil with resistivity range of 724-860Ωm, Silty sand with resistivity range of 163-494Ωm and Mudstone with resistivity range of 52-100Ωm. Results of Onicha-Oshiri lot show that the velocity values range from 1.28ms-1 to 1.95ms-1. Along profile D, velocity values rise from point 1 to point 3. Along the present bridge profile, the values are nearly the same for points 1 and 2 and rise to 1.37ms-1 at point 3. However along profile F, the velocity value is higher at point 2 (middle of the river). At Idembia site velocity values range from 0.634m s-1 to 0.99m s-1. Apart from profile B where the value is highest at point 3 (edge of the river) values at profiles A and C have higher amounts at the edges and lower amounts at the central portion indicating increased scouring at the edges. The river at Onicha-Oshiri site has higher velocity possibly on the account of this site being at the youthful stage of the river. At Onicha end, the top lateritic matter is interbedded with fresh blue shale which may be offensive to any structure. This must be taken care of during construction by aiming at the hard sandstone below.
Abstract: Pre-design Geoelectrical and River Velocity studies have been carried out at two bridge locations: Ebonyi River at Onicha-Oshiri road and Ebonyi River at Idembia Ezza. The objectives of the studies are to determine the geoelectrical parameters with respect to structure and rock type at these locations in combination with geology and carry out the a...
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Environmental Risk Management and Mitigation Strategies for Offshore Gas Well Drilling Projects (Case Study: Abu Qir Bay, Egypt)
Moussa Sobh Elbisy,
Ehab Abduraheem Mlybari
Issue:
Volume 2, Issue 2, April 2017
Pages:
66-77
Received:
15 March 2017
Accepted:
25 March 2017
Published:
12 April 2017
DOI:
10.11648/j.jccee.20170202.14
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Abstract: Risk evaluation for offshore gas exploration and production is a challenging task because much of the available data are highly uncertain and vague, and many of the drilling techniques are complex. The paper describes the implementation and use of environmental risk management and mitigation strategies for an offshore gas well drilling project. It includes an offshore case study from Abu-Qir Bay in the Egyptian sector of the Mediterranean. The environmental risk management study evaluated the potential impact of the operations and identified the mitigation procedures to be followed to eliminate any risk of contamination. It provides a framework for the future environmental management of the area in order to minimize the negative impacts of operations.
Abstract: Risk evaluation for offshore gas exploration and production is a challenging task because much of the available data are highly uncertain and vague, and many of the drilling techniques are complex. The paper describes the implementation and use of environmental risk management and mitigation strategies for an offshore gas well drilling project. It ...
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Simulating the Differential Positioning Mode Using One GPS Receiver
Ahmed Abobakr Elashiry,
Abdel Hameid M. Abdel Hameid
Issue:
Volume 2, Issue 2, April 2017
Pages:
78-86
Received:
10 March 2017
Accepted:
21 March 2017
Published:
14 April 2017
DOI:
10.11648/j.jccee.20170202.15
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Abstract: This research tends to raise the accuracy of absolute point positioning by simulating the differential positioning mode. This process was done by observing the unknown point using one unit GPS receiver after observing the fixed point with the same receiver and estimate the Doppler value; where it equals to the expected change at carrier phase measurement from two adjacent epochs, to determine the phase value in the following epoch and generate new observation file for the known point has phase observation at the same period of observing the unknown point. The generated data at the known point will be solved with the observed phase data at the unknown point for four satellites at least using triple difference technique to vanish the ambiguity value and all affecting errors on observations. Finally the least square technique will be applying on the resulted equations from the previous process. This method had been enhanced to improve the positioning accuracy from ten meters to 30 cm as a maximum error in 3D coordinates. In condition that there is one fixed point at least in the observation area, and the interval period between observing the fixed and unknown point is less than 15 min.
Abstract: This research tends to raise the accuracy of absolute point positioning by simulating the differential positioning mode. This process was done by observing the unknown point using one unit GPS receiver after observing the fixed point with the same receiver and estimate the Doppler value; where it equals to the expected change at carrier phase measu...
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