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  • 201.
    Hatem, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Emborg, Mats
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Nilsson, Martin
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Alireza, Pourbakhtiar
    Talc-based concrete for sealing borehole optimized by using particle packing theory2013Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 7, nr 4, s. 440-455Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The paper describes assessment of the performance of cement-poor concreteson the basis of packing theory. The concretes are intended for sealing segments of deep boreholes and have a small amount of cement for minimizing the mutual chemical impact on the contacting clay seals. The composition is examined by application of packing theory with respect to the cement/aggregate ratio and the gradation of the aggregate material which is crushed quartzite for providing high internal friction after maturation, as well as to talc added for fluidity and to the small amount of cement. Low porosity and micro-structural stability must be guaranteed for very long periods of time. The study exemplifies how packing theory assist designers in selecting optimal proportions of the various components. Optimum particle packing implies minimizing the porosity and thereby reducing the amount of cement paste needed to fill the voids between the aggregate particles. The use of talc as inorganic super-plasticizer since ordinary organic additives for reaching high fluidity at casting are undesirable, and since talc reacts with cement and provides high strength in along-term perspective.

  • 202.
    Hatem, Mohammed
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Pusch, Roland
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jonasson, Jan-Erik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Emborg, Mats
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Pourbakhtiar, Alireza
    Proportioning of cement-based grout for sealing fractured rock-use of packing models2013Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 5, nr 10, s. 765-774Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fractured, very permeable rock hosting repositories for radioactive waste will require grouting. New grout types of possible use where long-term performance is needed should have a small amount of cement for minimizing the increase in porosity that will follow from the ultimate dissolution and erosion of this component. They have to be low-viscous and gain strength early after injection and packing theory can assist designers in selecting suitable proportions of various grout components. Optimum particle packing means that the porosity is at minimum and that the amount of cement paste needed to fill the voids between aggregate particles is very small. Low porosity and microstructural stability must be guaranteed for long periods of time. Organic additives for reaching high fluidity cannot be used since they can give off colloids that carry released radionuclides and talc can be an alternative superplasticizer. Low-pH cement reacts with talc to give high strength with time while Portland cement gives early but limited strengthening. The clay mineral palygorskite can be used for early gelation because of its thixotropic properties. Once forced into the rock fractures or channels in soil it stiffens and serves as a filter that prevents fine particles to migrate through it be lost. However, its hydrophilic potential is too high to give the grout a high density and high strength. According to the experiments carried out most of the investigated grouts are injectable in fractures with apertures down to 100 μm.

  • 203.
    Hilo, Ali Nasser
    et al.
    Civil Engineering Department, Wasit University, Kut, Iraq.
    Saeed, Fouad Hussein
    Ministry of Water Resources, Kut, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Impact of Climate Change on Water Resources of Dokan Dam Watershed2019Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 11, nr 8, s. 464-474Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Lesser Zab is one of the most important tributaries of Tigris River. During the last few decades, the streamflow significantly decreased for long periods followed by extensive flood in short periods. This study aimed to quantify the impact of climate change on streamflow at Dokan Dam until year 2050 using SWAT model based on the scenario of medium emission (A1B) and five climate projection models. SWAT run using Climate Forecasting System Reanalysis (CFSR) was used as weather input data then calibrated and validated on monthly time step for the period from 1980 to 2013 with Nash-Sutcliff Ef- ficiency (NSE) of 0.73 and determination coefficient (R2) 0.73 for calibration processes. The data of this period is more reliable. The result indicated to a significant decrease on the projected streamflow until year 2050 with average streamflow for the six climate models of 167 m3/sec in past compared with the observed streamflow of 176.5 m3/sec for the base period (1980-2013). In addition,  the  study  shows  that most runoffs come  from Iranian  part of  the Dokan Dam Watershed with 65% of total simulated runoff. It is highly recommended  to  improve  the  efficiency  of  water  using  for  current  and  future water projects to meet the expected water shortage.

  • 204.
    Hou, Muzhou
    et al.
    School of Mathematics and Statistics, Central South University, Changsha, Hunan, China.
    Zhang, Tianle
    School of Mathematics and Statistics, Central South University, Changsha, Hunan, China.
    Weng, Futian
    School of Mathematics and Statistics, Central South University, Changsha, Hunan, China.
    Ali, Mumtaz
    School of Agricultural, Computational and Environmental Sciences Institute of Agriculture and Environment, University of Southern Queensland, Springfield, Australia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Yaseen, Zaher Mundher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Global Solar Radiation Prediction Using Hybrid Online Sequential Extreme Learning Machine Model2018Ingår i: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 11, nr 12, artikel-id 3415Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Accurate global solar radiation prediction is highly essential for related research on renewable energy sources. The cost implication and measurement expertise of global solar radiation

    emphasize that intelligence prediction models need to be applied. On the basis of long-term measured daily solar radiation data, this study uses a novel regularized online sequential extreme learning machine, integrated with variable forgetting factor (FOS-ELM), to predict global solar radiation at Bur Dedougou, in the Burkina Faso region. Bayesian Information Criterion (BIC) is applied to build the seven input combinations based on speed (Wspeed), maximum and minimum temperature (Tmax and Tmin), maximum and minimum humidity (Hmax and Hmin), evaporation (Eo) and vapor pressure deficiency (VPD). For the difference input parameters magnitudes, seven models were developed and evaluated for the optimal input combination. Various statistical indicators were computed for the prediction accuracy examination. The experimental results of the applied FOS-ELM model demonstrated a reliable prediction accuracy against the classical extreme learning machine (ELM) model for daily global solar radiation simulation. In fact, compared to classical ELM, the FOS-ELM model reported an enhancement in the root mean square error (RMSE) and mean absolute error(MAE) by (68.8–79.8%). In summary, the results clearly confirm the effectiveness of the FOS-ELM model, owing to the fixed internal tuning parameters.

  • 205.
    Huang, Yi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jia, Qi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    The one dimensional model for coarse particle around mining area in northern Sweden2012Ingår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 2, nr 2, s. 126-137Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Computational model had been established to predict the coarse dust transport rate within the Malmberget mining area in northern Sweden. Matlab GUI designing had been introduced to enhance the computation process. Certain modification methods were developed in order to improve the accuracy of the model. Dust retention time was calculated to estimate the dust transport in the suspension form. Field calibration proves the code works fairly well for the coarse dust in the research area.

  • 206.
    Huang, Yi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jia, Qi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    The simulation of the dust grain movement by sediment transport model around mining area in northern Sweden2012Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 2, nr 2, s. 1-11Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A simple sediment transport model has been utilized to simulate the dust grain movement in the area flow. The transport model can be used as a tool to estimate the dust grain transport situation in a mining area with consideration of the local topographical profile. The case study of the local dust characteristics survey proves the model works fairly well compared to the field calibration.

  • 207.
    Huda M., Madhloom
    et al.
    Mustansiriayah University, Baghdad- Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Geographical Information System and Remote Sensing for WaterResources Management Case Study: The Diyala River, Iraq2018Ingår i: International J. of Civil Engineering and Technology, ISSN 0976-6308, Vol. 9, nr 12, s. 971-984Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Utilizing Geographical Information System (GIS) in the management of water resources, especially, in the quality of surface water, constiytutes a worthwile attempt made in the improvement and control the levels of pollution in the water. In this paper, GIS technology was used in conjunction with Water Quality Index (WQI) to assess the suitability for onsumption of water in the souther within Baghdad City for human needs based on the set of monthly measurements during the period from January to December 2016. The variables measured in seven monitoring stations along the studied reach of the river were: Total Di

    (T.D.S), Total Hardness (T.H), Sulphate ion (SO Biochemical Oxygen Demand (BODhigher than the permissible limits specified by Iraqi and WHO regulations for the dand wet seasons. The digital pollution maps showed that the pollution moved from extremely polluted zones near the outfalls of wastewater to low polluted zones near the confluence of the Diyala and Tigris techniques are among the most effective methods to display the seasonal variability on

    water quality, which can be used by the decision makers.

  • 208.
    Hussain, Hussain M.
    et al.
    Department of Geology, Faculty of Science, University of Kufa.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Groundwater Pollution Potential in Part of the Western Desert, Iraq2015Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 5, nr 1, s. 1-17Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The growth of human population often corresponds with change in land use, including expansion of urban areas, which necessitates increasing the available amount of drinking water. As the surface water sources are more amenable to pollution, it has become necessary to use groundwater at an increasing rate. Groundwater is normally abundant in the alluvial region where the urban areas are often located. Such areas face a greater risk of pollution of groundwater due to several factors. Surface water resources are becoming more scares in Iraq which gave a tendency to use groundwater. In this research, groundwater vulnerability in part of the western desert had been studied. It was noticed that the area has low risk for the contamination of ground water.

  • 209.
    Hussain, Hussain Musa
    et al.
    Department of Geology, Faculty of Science, University of Kufa.
    Al-Haidarey, Mohammed
    Department of Ecology, Faculty of Science, University of Kufa.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Evaluation and Mapping Groundwater Suitability for Irrigation Using GIS in Najaf Governorate, Iraq2014Ingår i: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 22, artikel-id 4Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Irrigation Water Quality Index (IWQI) for groundwater within the Geographic Information System(GIS) environment is proposed so that it can be used in assessing the groundwater vulnerability. Themodel was applied to the Damman aquifer in the western part of Iraq. Thirty nine sites were chosen forthe investigation of the Damman aquifer. Triplicate ground water samples were collected from eachsite (during wet and dry seasons of 2013). Variables tested in each sample include: pH, EC, totalhardness Ca+2, Mg+2, Cl-, Na+ and SAR. The final water quality map constructed for the aquifershowed that there are three major regions. The first is in the northeastern part of the area while thesecond region is confined to the southeastern part. Finally, the third region extended along the westernpart of the study area. When this map was converted according to the suggested model, it showed thatthe water quality of the Damman aquifer is marginal for use for agriculture purposes.Journal

  • 210.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Khaleel, Moayad
    Mosul University.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Experimental Analysis of Sediment Deposition Due to Backwater Effect up-stream a Reservoir2014Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 8, nr 9, s. 1185-1193Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The phenomenon of aggradation due to sediment accumulation upstream reservoirs had been studied in this research. For this purpose, group of experiments were conducted in a laboratory channel 25 m long, 0.80 m wide and 0.70 m deep. A block was built at the end of the channel to work as a dam to impound water. The channel was supplied with drainage pipes on both sides to release water out in a manner similar to what happens in reservoirs. The bed of the channel was filled with sand of 0.80 mm median sieve diameter and 0.72 geometric standard deviation. The slope was 0.0093 for all experiments. Two sizes of sand were used representing the sediment. The median diameter and geometric standard deviation of the first were 0.365 mm and 0.46 respectively. The second sample had 0.65 mm median diameter and 0.67 standard deviation. A total of seventy experiments were conducted in two groups to examine effect the sediment transport rate, particle size of sediment and flow velocity on aggradation characteristics. The results showed that there is a strong linear direct relationship between aggradation elements (length and depth) with the rate of sediment transport. Group of dimensionless parameters affecting the aggradation characteristics were used to develop empirical equations to predict the length, maximum depth of aggradation and predict transient bed profile. The results of empirical approach were compared with the measurement data and previous numerical method. The results indicated that the percentage error was –19 to 31% for length of aggradation and –21 to 26% for maximum depth of aggradation. The results also showed that the sediment material were deposited closer to the body of the dam when the released water from the dam is higher than the inflow.

  • 211.
    Issa, Issa E
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment of Sedimentation Characteristics and Capacity Curve for Mosul Dam Reservoir, Iraq2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    The sedimentation process is the most important problems that affect directly the performance of reservoirs due to the reduction of the storage capacity and possible problems effecting the operation. Thus periodic assessment of the storage capacity and determining sediment deposition patterns is an important issue for operation and management of reservoirs. In this study, bathymetric survey results had been used to assess the characteristics of sedimentation of Mosul Reservoir. It is located on the Tigris River in the north of Iraq. The water surface area of its reservoir is 380 km2 with a designed storage capacity of 11.11 km3 at a maximum operating level (330 m a.s.l). The dam started operating in 1986. No detailed study was yet carried out to assess its reservoir. The present study indicated that the annual sediment deposited in the reservoir is 45.72 × 106 m3year-1 which is divided into 23.2 × 106 and 22.52 × 106 m3year-1 for dead and live zones respectively. This implies the annual reduction rate in the dead and live storage capacities of the reservoir is 0.786% and 0.276% respectively. Furthermore, the stage-storage capacity curves for the future periods (prediction curves) were assessed using 2011 bathymetric survey data.

  • 212.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment sedimentation rate in the Mosul dam reservoir, Iraq2013Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Mosul dam is one of the biggest hydraulic structures in Iraq that was built on the Tigris River 60 km north-west Mosul city north of Iraq. The water surface area of its reservoir is 380 km2 with a storage capacity of 11.11×109 m3 at a maximum operation level (330 m.a.s.l). The dam became operational in 1986. No study has been conducted to determine the sedimentation rate, storage capacity and new operational curve since that date. To develop an up to date operational curve, a new bathymetric survey was conducted in 2011. The results indicated that the reduction in the storage capacity of the reservoir was 10.29 %. This implies that the annual sedimentation rate within the reservoir was 45.72×106 m3.yr-1 (0.41%) that is less than the average worldwide rate. Consequently, a new operational curve was constructed.

  • 213.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Changes in bed morphology of Mosul dam reservoir2013Ingår i: Journal of Advanced Science and Engineering Research, ISSN 2231-8844, Vol. 3, nr 2, s. 86-95Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mosul dam is one of the biggest hydraulic structures in Iraq. It was constructed on the Tigris River in the north of Iraq for multiple purposes: irrigation, flood control and power generation. The initial storage capacity and water surface area of its reservoir reach 11.11 km3 and 380 km2 respectively at the maximum operation level 330 m.a.s.l. The dam was operated in 1986. Since that time no survey has been conducted to determining the characteristics of sedimentation in the reservoir. Blockage of the intakes of the pump station for North Al-Jazira Irrigation Project in Mosul dam reservoir has highlighted the importance of sedimentation problems within the reservoir.Sediment distribution was studied within the reservoir. A comparison was made between the conditions at the start of the dam operation and a recent bathymetric survey conducted in 2011.The former was achieved using a topographic map scale 1: 50000 dated 1983 which was converted to a triangular irregular network (TIN) format using the Arc/GIS program. The results of the bathymetric survey were also converted to the TIN map format using the above program. Comparison of the two maps shows that the sedimentation magnitude in the upper zone of the reservoir, where the River Tigris enters, was highest and gradually reduced toward Mosul dam site. Maximum deposition thickness within the reservoir was 17.6 m. The thalweg bed slope of the River Tigris within reservoir area changed from 0.65 m.km-1 before dam construction to 0.71 m.km-1 on the 2011 survey. Zones within the

  • 214.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Mosul Dam Resorvoir Sedimentation Characteristics, Iraq2014Ingår i: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 22, artikel-id 3Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sediment transported by rivers and finally deposited in reservoirs directly affects dam performanceand causes a reduction in their storage capacity and hence operating efficiency. In this study, thesedimentation characteristics of Mosul dam reservoir have been evaluated using two topographic mapsof the reservoir area at different times (1986 and 2011) via Arc/GIS software. The dam is located on theTigris River in the northern part of Iraq and started operating in 1986. The water surface area of itsreservoir is 380 km2 with a designed storage capacity of 11.11 km3 at a maximum operating level (330m a.s.l). The results showed that the annual sediment deposition rate is 45.72 × 106 m3 year-1 of which23.2 × 106 and 22.52 × 106 m3 year-1 are in the dead storage and live storage zones respectively. As aconsequence, the live and dead storage zones lost 6.9% and 19.66% respectively of their storagecapacity during the 25 year of operation of the dam. The water-spread area (water surface area) of thereservoir at dead storage level (300 m a.s.l) was reduced annually by about 1.34 km2. Furthermore,the stage-storage capacity curves for future periods (prediction curves) were assessed and comparedwith adopted prediction curves using 2011 bathymetric survey data.

  • 215.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sedimentation and new operational curves for Mosul Dam, Iraq2013Ingår i: Hydrological Sciences Journal, ISSN 0262-6667, E-ISSN 2150-3435, Vol. 58, nr 7, s. 1456-1466Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mosul dam is one of the biggest hydraulic structures in Iraq. Its storage capacity is 11.11×109 m3 at a maximum operation level 330 m of a.s.l. The dam became operational in 1986 and no survey has been conducted to determine its storage capacity and establish new operational curves since this date. In this research topographic map scale 1: 50000 dated 1983 was converted to triangulated irregular network (TIN) format using the Arc/GIS program to evaluate the operational curves. Then the reservoir was surveyed in 2011 to establish the reduction in its storage capacity and to develop new operational curves. The results indicated that the reduction in the storage capacity of the reservoir was 14.73%. This implies that the rate of sedimentation within the reservoir was 45.72×106 m3.yr-1. The results indicated that most of the sediment was deposited within the upper zone of the reservoir where the River Tigris enters the reservoir.

  • 216.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Khaleel, Moayad
    Mosul University.
    Sediment delivered in the upper part of Mosul reservoir using physical model2012Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 6, nr 11, s. 1544-1550Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mosul dam is the biggest hydraulic structure in Iraq located on the River Tigris 60 km northwest of Mosul city. Its storage capacity is 11.11 × 109 m3 and it had been in operation since 1986. A physical distorted model with movable bed having a vertical scale 1:100 and a horizontal scale 1:1000 was used to conduct the experiments relating the water level at the reservoir and water discharge upstream the reservoir with the bed load transport rate. The model represents the first 15 km of most northern part of Mosul dam reservoir. The construction of the model was based on bathymetric survey conducted in 2009. Twenty-four experiments were executed using four different discharges (0.5, 1.0, 1.5, and 2.0 L/s) which represent the average discharges in the flood period of River Tigris. At each individual discharge six operations were assumed where the reservoir’s water level was 305, 307, 309, 310, 312, 315 meters above sea level respectively. In all the experiments conducted, bedload transport was measured in the physical model at section representing the River Tigris 1 km upstream the reservoir. The results showed that the bedload rate was decreasing when the water level within the reservoir was increasing. It was also evident that bedload transport rate dramatically decreased at level 310 meter above sea level onward. This is due to the fact that at this level represent the effect of backwater which was noticeable on the river cross section.

  • 217.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Khaleel, Moayad
    Mosul University.
    The effect of operation of Mosul dam on sediment transport in its reservoir2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    Mosul dam is the biggest hydraulic structure in Iraq located on the River Tigris 50 Km north of Mosul city. Its storage capacity is 11.1 x 109 m3 and it had been in operation since 1986.A physical model representing the most northern part of Mosul dam reservoir was used to conduct the experiments. The construction of the model was based on field survey conducted in 2010. Twenty-four experiments were executed using four different discharges (500, 1000, 1500 and 2000 m3/s respectively). At each individual discharge six operations were assumed where the reservoirs water level was 305,307,309,310, 312, 315 MSL respectively. In all the experiments conducted, bedload transport rate was decreasing when the water level within the reservoir was increasing. It was also evident the bedload transport rate dramatically decreased at level 310 onward. This is due to the fact that at this level the effect of backwater was noticeable on the river cross section

  • 218.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sherwany, Govand
    Ministry of Higher Education and Scientific Research—KRG, Erbil.
    Monitoring and Evaluating the Sedimentation Process in Mosul Dam Reservoir Using Trap Efficiency Approaches2015Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 7, nr 4, s. 190-202Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Reservoirs are usually exposed to sediment accumulation problems that will lead to reduction in their storage capacity. This problem directly affects the performance of the dams and causes shortage of their useful life. The simplest technique to estimate sediment deposition rate is using sediment rating curve with sediment trapping efficiency (TE) of the reservoir. Many empirical and semi-empirical approaches have been suggested for to determine this term depending on the annual inflow rate, reservoir characteristics and features of the catchments area. In this study six different empirical methods depending on the residence time principle (water retention time) were used. These approaches were reviewed and applied to determine TE of Mosul dam reservoir (MDR) for period 1986 to 2011. The monthly operating data for inflow, outflow and water elevations for MDR were used to determine monthly TE and long-term TE for whole period of MDR using the mentioned methods. Furthermore, the monthly inflow rate for River Tigris upstream MDR, its sediment rating curve and sediment feeding from valleys around MDR were used to estimate the amount sediment coming to the reservoir. The results provided by these methods for TE withsediment coming to MDR were used to compute the amount of sediment deposited in MDR on monthly bases during this period. The results obtained were evaluated using observed bathymetric survey data that had been collected in 2011 after 25 years of the operation of the dam. The results showed all the mentioned methods gave convergent results and they were very close to bathymetric survey results for estimating the volume of sediment deposited especially that proposed by Ward which gave 0.368% percentage error. Furthermore, the result computed using monthly TE gave good agreement if compared with that long-term TE where the percentage error was ranging between −3.229% to 1.674% for monthly adopted data and −4.862% to −2.477% for whole period data. It is believed that this work will help others to use this procedure on other reservoirs.

  • 219.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sherwany, Govand
    Ministry of Higher Education and Scientific Research, Kurdistan Region.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Expected Future of Water resources within Tigris–Euphrates Rivers basin, Iraq2014Ingår i: Journal of Water Resource and Protection, ISSN 1945-3094, E-ISSN 1945-3108, Vol. 6, nr 5, s. 421-432Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Iraq is one of the riparian countries within basins of Tigris-Euphrates Rivers in the Middle East region. The region is currently facing water shortage problems due to the increase of the demand and climate changes. In the present study, average monthly water flow measurements for 15 stream flow gaging stations within basins of these rivers in Iraq with population growth rate data in some of its part were used to evaluate the reality of the current situation and future challenges of water availability and demand in Iraq. The results showed that Iraq receives annually 70.92 km3 of water 45.4 and 25.52 km3 from River Tigris and Euphrates respectively. An amount of 18.04 km3 of the Tigris water comes from Turkey while 27.36 km3 is supplied by its tributaries inside Iraq. The whole amount of water in the Euphrates Rivers comes outside the Iraqi borders. Annual decrease of the water inflow is 0.1335 km3 year-1 for Tigris and 0.245 km3 year-1 for Euphrates. This implies the annual percentage reduction of inflow rates for the two rivers is 0.294% and 0.960% respectively. Iraq consumes annually 88.89% (63.05 km3) of incoming water from the two rivers, where about 60.43 and 39.57 % are from Rivers Tigris and Euphrates respectively. Water demand increases annually by 1.002 km3; of which 0.5271 km3 and 0.475 km3 within Tigris and Euphrates basins respectively. The average water demand in 2020 will increase to 42.844 km3 year-1 for Tigris basin and for Euphrates 29.225 km3 year-1 (total 72.069 km3 year-1), while water availability will decrease to 63.46 km3 year-1. This means that the overall water shortage will be restricted to 8.61 km3.

  • 220.
    Issa, Issa E.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sherwany, Govand
    Ministry of Higher Education and Scientific Research, Kurdistan Region.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sedimentation processes and useful life of Mosul dam Reservoir, Iraq2013Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 5, nr 10, s. 779-784Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The sedimentation process is the most important problems that affect directly the performance of reservoirs due to the reduction of the storage capacity and possible problems effecting the operation. Thus periodic assessment of the storage capacity and determining sediment deposition patterns is an important issue for operation and management of the reservoirs. In this study, bathymetric survey results and an analytical approach had been used to assess the characteristics of sedimentation and estimate the useful life of Mosul Reservoir. It is located on the Tigris River in the north of Iraq. The water surface area of its reservoir is 380 km2 with a designed storage capacity of 11.11 km3 at a maximum operating level (330 m a.s.l). The dam started operating in 1986. No detailed study was yet carried out to assess its reservoir. The present study indicated that the annual reduction rate in the dead and live storage capacities of the reservoir is 0.786% and 0.276% respectively. The observed results (bathymetric survey) and algebraic formula show approximately that the useful life of Mosul dam reservoir is about 125 years. Furthermore, the stage-storage capacity curves for the future periods (prediction curves) were established using bathymetric survey data.

  • 221.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dust emission from unpaved roads in Luleå, Sweden2013Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 3, nr 1, s. 1-13Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The dust emission from unpaved roads, if not controlled, can cause enormous problems. Though a few real-world measurements of road dust have been done by automated samplers in Sweden, measurement by BSNE (Big Spring Number Eight) and the estimation of total dust generation from vehicle driving is rare. This study measured and analyzed dust emission by BSNE at two unpaved roads in Luleå, Sweden, at the driving speed of 20, 30, 40, and 50 km/h different heights. Even though US EPA excluded vehicle speed as a parameter in estimating dust emission factors for unpaved roads, this study confirmed a strong dependence of dust emission on vehicle speed. This is in agreement with several recent studies which concluded dust emission increases with driving speed exponentially or linearly, however the power law is the best description for the data from this study. The comparison with estimated dust emission by US EPA’s equation showed the equation underestimates the dust emission more than 50 percent when vehicle speed and silt content is higher than 25.40km/h and 2.17 percent respectively. There might be some interrelationship between driving speed and silt content in road surface.Earlier researchers have reported increased dust emission with increasing silt content and this is confirmed by this study.

  • 222.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dust generation within the vicinity of Malmberget mine, Sweden2011Ingår i: Applied Mechanics and Materials, ISSN 1660-9336, E-ISSN 1662-7482, Vol. 90-93, s. 752-759Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mining activities are usually associated with environmental impacts, particularly that of air pollution by fugitive dust. Malmberget mine is one of the most important iron mines in Sweden and the dust problem has been noticed by the inhabitants for a long time. Dust collectors had been installed to measure the dust fallout around the mining site. In this research the dust fallout recorded during the period August 2006 till July 2010 were analyzed. Generally speaking the amount of dust fallout was decreasing year by year due to some implemented dust control methods. Mining activities produced more dust during summer than winter. The peak value was 265g/100m2/30d appeared in May 2007, and the lowest dust fallout was 25g/100m2/30d happened in August 2009. Dust was determined to be originated from the open pit area and the industrial center area. Truck transportation on the haul roads, wind erosion of stockpiles and exposed areas were the main activities that caused dust generation.

  • 223.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Estimation of road dust using BSNEs2013Ingår i: Natural Science, ISSN 2150-4091, E-ISSN 2150-4105, Vol. 5, nr 5, s. 567-572Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mining is a core industry in Sweden and plays an important role in the economic development of the country. Though the importance of mining dust has been well recognized, the quantification of dust production with regard to individual source activity has rarely been done in Sweden. Depending on the type of source activity, dust estimation method can be chosen from three alternatives: exposure profiling methods, back calculation method, and wind erosion prediction method. Also included in the paper is an example of experiment, which was executed on two unpaved roads in Lulea, Sweden by using exposure profiling method. The experiment concluded that dust emission due to vehicle transportation is strongly dependent on traveling speed and road bed material.

  • 224.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Evaluation of dust fallout at malmberget mine, Sweden for the period August 2009 to August 20102011Ingår i: Journal of Advanced Science and Engineering Research, Vol. 1, nr 2, s. 246-260Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dust is produced when mining operations take place. The transportation and deposition of dust depend mainly on climatic factors, as well as land surface characteristics. Malmberget mine operated by Luossavaara-Kiirunavaara Aktiebolag is one of the most important iron mines in Sweden. The mining area includes an area with a huge open pit and an industrial center. Both sites are surrounded by residential areas where people are suffering from dust problems. The collected dust from 26 measuring stations during the period 2001 to 2010 has been analyzed using the surfer 9.0 program. Generally speaking the dust fallout in summer was higher than that in winter and the volumes decreased through time as a result of implemented dust control methods. Analysis of the data from August 2009 to August 2010 indentified two sources of dust generation. One was located close to the open pit, and the other near the current mining industrial center. Among all the measuring stations, the maximum and minimum values within the year were 1284 g/100m2/30d and 9 g/100m2/30d, respectively. Dust production around the Malmberget mine was attributed to three reasons, namely, wind erosion of the exposed area close to the open pit, truck transportation on haul roads, and wind erosion of stockpiles. In addition to climatic factors, the variation of dust detected depended on mining activities and road construction.

  • 225.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Measurement of dust emission from a road construction using exposure-profiling method2013Ingår i: Journal of Natural Science, ISSN 0075-4307, Vol. 5, nr 12, s. 1255-1263Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Road construction is one example of heavy constructions that may have a substantial temporary impact on local air quality. Construction of Luleå Road during the summer 2013 generated a great deal of dust emission. US EPA recommended exposure-profiling method was used to measure dust emission. Inexpensive BSNE dust samplers were used instead of high volume samplers. The objective was to give a general idea of the amount of dust generated due to the construction work. Dust generation related to weather was discussed conditions. Estimated threshold wind velocity for road surface materials at the height of 2m were 12.88m/s, 12.88m/s and 24.76m/s which were lower measured wind velocity, indicated no dust generated from wind erosion. Dust masses for 7 sampling periods show dust generation had a close relation with moisture content of surface material. Wind speed, humidity had minor or no effect. The estimated dust emission rate in the construction work during the measuring period was 22.86kg TSP/d, 6kg/d was from construction work and 16.86kg/d was generated due to traffic on temporary roads.

  • 226.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Modeling of wind erosion of the Aitik tailings dam using SWEEP model2014Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 6, nr 7, s. 355-364Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Waste impoundments are usually not protected by any growing crops, soil roughness, or wind barriers, and dust due to wind erosion of the surface waste material can be a major environmental problem. The tailings dam in Aitik is highly susceptible to wind erosion when it is dry and windy. Strong dust storms may occur during dry seasons. These events are short-lived but may transport a huge amount of particulate matter and adversely impact air quality in downwind areas. This study estimated material loss from the Aitik tailings dam using SWEEP model. The simulated total material loss, saltation and creep loss, suspension loss and PM10 loss were 4.4941kg/m2, 0.042 kg/m2, 4.4559 kg/m2, 0.264057 kg/m2 respectively. To control the dust generation wind breaks could be suggested to be installed at 800m downwind the upwind edge of the tailings dam to reduce the saltation and creep and it would in turn reduce suspended emission. The measured total suspended material for five days by exposure profiling method was 0.475kg/m2, which had a big difference with simulate a value of 4.4559 kg/m2. Many reasons contributed to the disagreement of simulated value and measured value in this study. In order to use the model for mining industry more tests are needed to validate the modeling result and calibration methods could be useful in adjusting the internal coefficients and empirical equations.

  • 227.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Huang, Yi
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dust emissions from landfill deposition: a case study in Malmberget mine,Sweden2013Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 3, nr 3, s. 25-34Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A great amount of industrial wastes are produced in Sweden every year. In 2008 there were 97.9 million tons of wasted generated, among which 93 million tons industrial waste were produced. 64.1% of industrial wastes were deposited in the landfill sites. Dust generation is one of the most important problems associated with industrial waste and landfills. The particulate dust emissions come from the industrial waste may contain heavy metal and produce environmental problems and potential health risks. Active and passive samplers, deposition pans are common equipment to collect dust samples. Real-time monitors use laser diffraction to recording continuous dust concentration. Dust emission from Malmberget mine in Sweden was analyzed as a case study. Dust was collected by NILU deposit gauge from 26 stations. Generally speaking the amount of dust fallout was decreasing with time because of implemented dust control methods. During the period August 2009 to August 2010, among all the measuring stations through the year, the maximum and the minimum value were 1284 g/100m2/30d and 9 g/100m2/30d. Two sources of dust generation were identified. The first was located close to the open pit, and the second near the current mining industrial center. The dust generation due to road construction was calculated.

  • 228.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Huang, Yi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Dust emissions from landfill due to deposition of industrial waste: a case study in Malmberget mine, Sweden2011Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    A great amount of industrial wastes are produced in Sweden every year. In 2008 there were 97.9 million tons of wasted generated, among which 93 million tons industrial waste were produced. 64.1% of industrial wastes were deposited in the landfill sites. Dust generation is one of the most important problems associated with industrial waste and landfills. The particulate dust emissions come from the industrial waste may contain heavy metal and produce environmental problems and potential health risks. Active and passive samplers, deposition pans are common equipment to collect dust samples. Real-time monitors use laser diffraction to recording continuous dust concentration. Dust emission from Malmberget mine in Sweden was analyzed as a case study. Dust was collected by NILU deposit gauge from 26 stations. Generally speaking the amount of dust fallout was decreasing with time because of implemented dust control methods. During the period August 2009 to August 2010, among all the measuring stations through the year, the maximum and the minimum value were 1284 g/100m2/30d and 9 g/100m2/30d. Two sources of dust generation were identified. The first was located close to the open pit, and the second near the current mining industrial center. The dust generation due to road construction was calculated. On the other hand dust generation was also closely related to weather conditions.

  • 229.
    Jia, Qi
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Huang, Yi
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Particle characterization and determination of erodible fraction of surface soil nearby the open pit in Malmberget mine, Sweden2011Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Wind erosion of soil from exposed areas in mining sites is one of the sources for dust generation. Particle size distribution and mineralogical composition of source soil, erodible fraction of surface soil, moisture, as well as organic matter content are important factors that determine the property of particulate generation process. In this research four soil samples were taken using shovel at different depth from the edge of the pit and the surface area nearby the pit in Malmberget mine in Sweden. Soil samples were analyzed for density, particle size, mineralogical composition, organic matter content, and CaCO3 content. No calcite was detected by Qemscan and consequently, CaCO3 was assumed absent in the soil samples. Moisture contents in the surface samples were too little to prevent soil from wind erosion. All soil samples were mainly composed of albite, quartz, and K felspar. Miner minerals such as mineral 23 (bFe, bCa), as well as grossular, were more abundant within the surface samples while the reverse is true for ilment. It should be mentioned, however, that undersurface samples contained more particles of 100 μm in diameter compared to surface samples. Measured erodible fractions for surface samples were 35.9% and 43.39%. The erodible fraction was calculated for the soil of the studied area but the equations could not be applied because the calculated values were overestimated. The value of soil erodibility index was determined to be 19t/acre which was wind erosion group 7. Since wind erosion group 7 is not a highly intrinsic erodible soil group, the dust problem might also arise from disturbances of soil surface soils by trucks and other construction activities around the open pit.

  • 230.
    Jing, Wang
    et al.
    Department of Computer science, Baoji Universi ty of Arts and Sciences, Baoji, China. Faculty of Computer Systems & Software Engineering, University Malaysia Pahang, Pahang, Malaysia .
    Naji, Hafeth Ibrahem
    Department of civil Engineering, College of Engineering, University of Diyala, Diyala, Iraq.
    Zehawi, Raquim Nihad
    Department of civil Engineering, College of Engineering, University of Diyala, Diyala, Iraq.
    Ali, Zainab Hasan
    Department of civil Engineering, College of Engineering, University of Diyala, Diyala, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Yaseen, Zaher
    Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam .
    System Dynamics Modeling Strategy for Civil Construction Projects: The Concept of Successive Legislation Periods2019Ingår i: Symmetry, ISSN 2073-8994, E-ISSN 2073-8994, Vol. 11, nr 5, s. 1-18, artikel-id 677Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cost and time performance are considered to be the most important aspects in the construction industry. The exceptional conditions that took place in Iraq since the beginning of the third millennia had a huge vicious impact on the cost and time performance of local constructionprojects. This may represent the principal motivation for the local authorities to enact some four successive legislations in order to control the performance of the construction industry. In this research, an evaluation is made to the cost and time performance of local construction projects and their variation due to the multiple changes in the internal factors that affect project performance,and changes in the surrounding events include legislative, economic, and security environment during the period that lasted from 2003 to 2014. Data is collected from 30 governmental projects to conduct the evaluation. A comprehensive questionnaire is performed to estimate a quantitative value for the impact of several factors that concern both the owner and the contractor, with special consideration to their variation through the successive legislation periods. These estimates are, in turn, utilized in a system dynamics model, in which the project development process is simulated.

    The final cost and duration changes in the project are accumulated in the form of stocks to give an indication of the cost and time performance of the project. The developed model returned a progressive reduction of 10.9% for the change in project cost and 135.37% for the change in project schedule throughout the eleven years period.

  • 231.
    Jing, Wang
    et al.
    Department of Computer Science, Baoji University of Arts and Sciences, Shaanxi, People’s Republic of China. Faculty of Computer Systems & Software Engineering, University Malaysia Pahang, Pahang, Malaysia.
    Yaseen, Zaher Mundher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Shahid, Shamsuddin
    School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Saggi, Mandeep Kaur
    Department of Computer Science, Thapar Institute of Engineering and Technology, Patiala, India.
    Tao, Hai
    Department of Computer Science, Baoji University of Arts and Sciences, Shaanxi, People’s Republic of China.
    Kisi, Ozgur
    Faculty of Natural Sciences and Engineering, Ilia State University, Tbilisi, Georgia.
    Salih, Sinan Q.
    Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Chau, Kwok-Wing
    Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, People’s Republic of China.
    Implementation of evolutionary computing models for reference evapotranspiration modeling: short review, assessment and possible future research directions2019Ingår i: Engineering Applications of Computational Fluid Mechanics, ISSN 1994-2060, E-ISSN 1997-003X, Vol. 13, nr 1, s. 811-823Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Evapotranspiration is one of the most important components of the hydrological cycle as it accounts for more than two-thirds of the global precipitation losses. Indeed, the accurate prediction of reference evapotranspiration (ETo) is highly significant for many watershed activities, including agriculture, water management, crop production and several other applications. Therefore, reliable estimation of ETo is a major concern in hydrology. ETo can be estimated using different approaches, including field measurement, empirical formulation and mathematical equations. Most recently, advanced machine learning models have been developed for the estimation of ETo. Among several machine learning models, evolutionary computing (EC) has demonstrated a remarkable progression in the modeling of ETo. The current research is devoted to providing a new milestone in the implementation of the EC algorithm for the modeling of ETo. A comprehensive review is conducted to recognize the feasibility of EC models and their potential in simulating ETo in a wide range of environments. Evaluation and assessment of the models are also presented based on the review. Finally, several possible future research directions are proposed for the investigations of ETo using EC.

  • 232.
    Karim, Kamal
    et al.
    Sulaimani University.
    Sissakian, Varoujan
    Consultant Geologist, Erbil.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Effect of the Sun Radiation on the Asymmetry of Valleys in Iraqi Zagros Mountain Belt (Kurdistan Region)2014Ingår i: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 4, nr 2, s. 23-32Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The geomorphological feature of the valley's asymmetry is described in the Western Zagros in Iraqi Kurdistan; in terms of facing of the valley sides relative to the position of the sun. The asymmetry is represented by steeper northwest facing valley sides; as compared to the southeast facing sides. This feature shows clear valley's asymmetry in cross section is a new geomorphological characteristic for the Western Zagros Mountain Belt. The asymmetry of valleys, in the present study, is proved to exist in different rock types and areas, which is developed by more chemical weathering of one facing sides relative to the other side. The weathering is attributed to the remaining of the moisture for longer time than the southeastern sides, which are stroke by sun radiation for longer time and are dried more rapidly. A simple method was established for indicating the steeper side of the valleys. The method consists of drawing two parallel lines across the photo of the valley, then connecting the bottom of the valley with the left and right deflection points on the inter-valleys ridges by lines. Finally the angles between the lower horiozontal line and inclined lines are measured, which indicates the asymmetry of the valleys.

  • 233.
    Kheiralipour, Kamran
    et al.
    Mechanical Engineering of Biosystems Department, Ilam University.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sissakian, Varoujan
    Department of Natural Resources, Engineering and Management. University of Kurdistan, Hewler, KRG, Iraq.
    Dust determination methods and instrumentations2018Ingår i: 2nd InternationalConference on Dust: 2nd InternationalConference on Dust, 2018Konferensbidrag (Refereegranskat)
    Abstract [en]

    In recent years, different aspects of dust storm, as one of the environmental problems, have been investigated by

    many researchers. One of the main goals in this regard is controlling of the dust and its subsequent hazards. The

    first step in the controlling process of dust or its hazards is detection of dust as well as determination of dust

    concentration. There are different methods and devices to determine dust concentration. In the work, the

    existing methods and devices to measure the dust concentration in the environment have been presented and

    explained. Furthermore, the potential application of image processing technique as a low cost method to

    determine dust concentration has been discussed.

  • 234.
    Li, Jing
    et al.
    Business School, Lanzhou City University, Lanzhou, China.
    Ameen, Ameen Mohammed Salih
    Department of Water Resources, University of Baghdad, Baghdad, Iraq.
    Mohammad, Thamer Ahmad
    Department of Water Resources, University of Baghdad, Baghdad, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Yaseen, Zaher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    A Systematic Operation Program of a Hydropower Plant Based on Minimizing the Principal Stress: Haditha Dam Case Study2018Ingår i: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 10, nr 1270, s. 2-20Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dam operation and management have become more complex recently because of the need for considering hydraulic structure sustainability and environmental protect on. An Earthfill dam that includes a powerhouse system is considered as a significant multipurpose hydraulic structure. Understanding the effects of running hydropower plant turbines on the dam body is one of the major safety concerns for earthfill dams. In this research, dynamic analysis of earthfill dam, integrated with a hydropower plant system containing six vertical Kaplan turbines (i.e., Haditha dam), is investigated.In the first stage of the study, ANSYS-CFX was used to represent one vertical Kaplan turbine unit by designing a three-dimensional (3-D) finite element (FE) model. This model was used to differentiate between the effect of turbine units’ operation on dam stability in accordance to maximum and minimum reservoir upstream water levels, and the varying flowrates in a fully open gate condition. In the second stage of the analysis, an ANSYS-static modeling approach was used to develop a 3-D FE earthfill dam model. The water pressure pattern determined on the boundary of the running turbine model is transformed into the pressure at the common area of the dam body with turbines. The model is inspected for maximum and minimum upstream water levels. Findings indicate that the water stress fluctuations on the dam body are proportional to the inverse distance from the turbine region. Also, it was found that the cone and outlet of the hydropower turbine system are the most affected regions when turbine is running. Based on the attained results, a systematic operation program was proposed in order to control the running hydropower plant with minimized principal stress atselected nodes on the dam model and the six turbines.

  • 235.
    Lindblom, Jenny
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Madhlom, Qais
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Possibilities of reducing energy consumption by Optimization of Ground Source Heat Pump Systems in Babylon, Iraq2016Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 3, s. 130-139Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Iraq is located in the Middle East with an area that reaches 437072 km2 and a population of about 36 million. This country is suffering from severe electricity shortage problems which are expected to increase with time. In this research, an attempt is made to minimize this problem by combining the borehole thermal energy storage (BTES) with a heat pump, the indoor temperature of a residential building or other facility may be increased or reduced beyond the temperature interval of the heat carrier fluid.Due to the relatively high ground temperature in Middle Eastern countries, the Seasonal thermal energy storages (STES) and Ground Source Heat Pump (GSHP) systems have a remarkable potential, partly because the reduced thermal losses from the underground storage and the expected high COP (ratio of thermal energy gain to required driving energy (electricity)) of a heat pump, partly because of the potential for using STES directly for heating and cooling. In this research, groundwater conditions of Babylon city in Iraq were investigated to evaluate the possibility of using GSHP to reduce energy consumption. It is believed that such system will reduce consumed energy by about 60%.

  • 236.
    Loffill, Ed
    et al.
    Liverpool JM University.
    Alkhaddar, Rafid
    Liverpool JM University.
    Phipps, David
    Liverpool JM University.
    Andoh, Robert
    Hydro International UK.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Aerated CoUFS: A pilot scale study into the impacts of changing variables on nitrication performance2013Ingår i: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 21Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper describes the findings of a long term study of the nitrification performance of apurpose built, large-scale, pilot plant consisting of two mirrored, aerated, continuouslyoperated upflow filters (ACoUFs) operating under realistic conditions. The effect oftemperature, liquid flow rate, aeration rate and media types on the performance of each ofthese filters is reported. After a start-up period of 2-3 weeks each plant performed consistentlyand the performance, expressed as a concentration change between influent and effluent, wasfound to depend directly on temperature and aeration but inversely on flow rate, with littleinteraction between the variables. The introduction of these aerated CoUF variants can havea considerable role to play in increasing effluent quality.

  • 237.
    Lundberg, Angela
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Feiccabrino, James
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Westerlund, Camilla
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Urban snow deposits versus snow cooling plants in northern Sweden: A quantitative analysis of snow melt pollutant releases2014Ingår i: Water quality research journal of Canada, ISSN 1201-3080, Vol. 49, nr 1, s. 32-42Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    High-velocity runoff from snow deposit transports suspended grain-attached contaminants while underground snow storages trapped these contaminants within the storage. The aim here is to quantify pollutant masses from an urban snow deposit and to investigate the conditions when pollutant control was increased by turning a snow deposit into a snow cooling plant with permeable underground snow storage. Pollutant masses in an urban snow deposit in northern Sweden were: Cu = 67, Pb = 17, Zn = 160, P = 170, SS = 620, 000, Cl = 1, 200, N = 380 kg. A theoretical analysis showed that the fraction of surface runoff from a surface deposit largely depends on the hydraulic conductivity (K, m s-1) of the soil. For a melt rate of 30 mm, day-1, surface runoff would be about 97% for a soil with K = 10-8, while nonexistent for K>10-6. Similar soil conductivities are needed to ensure that all snow melt could be transported as groundwater from an underground storage. The largest pollution-control advantage with underground snow storage compared to a surface deposit would thus be that piping and filters for operation of the plant could be used to filter surface snow melt runoff before rejection

  • 238.
    Madhloom, Huda M.
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Department of Civil Engineering, Al-Mustansiriayah University, Baghdad 1001, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Laue, Jan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Chabuk, Ali
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Department of Environment Engineering, College of Engineering, University of Babylon, Babylon 51002, Iraq.
    Modeling Spatial Distribution of Some Contamination within the Lower Reaches of Diyala River Using IDW Interpolation2018Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 10, nr 1, artikel-id 22Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this research was to simulate the water quality along the lower course of theDiyala River using Geographic Information Systems (GIS) techniques. For this purpose, the samples were taken at 24 sites along the study area.  The parameters:  total dissolved solids (T.D.S), total suspended solids (T.S.S), iron (Fe), copper (Cu), chromium (Cr), and manganese (Mn) were considered. Water samples were collected on a monthly basis for a duration of five years. The adopted analyzing approach was tested by calculating the mean absolute error (MAE) and the correlation coefficient(R) between observed water samples and predicted results. The result showed a percentage error less than 10% and significant correlation at R > 89% for all pollutant indicators.  It was concluded that the accuracy of the applied model to simulate the river pollutants can decrease the number of monitoring station to 50%. Additionally, a distribution map for the concentrations’ results indicatedthat many of the major pollution indicators did not satisfy the river water quality standards.

  • 239.
    Malik, Anurag
    et al.
    Department of Soil and Water Conservation Engineering, College of Technology, G.B. Pant University of Agriculture & Technology, Pantnagar, Uttarakhand, India.
    Kumar, Anil
    Department of Soil and Water Conservation Engineering, College of Technology, G.B. Pant University of Agriculture & Technology, Pantnagar, Uttarakhand, India.
    Kushwaha, Daniel Prakash
    Department of Soil and Water Conservation Engineering, College of Technology, G.B. Pant University of Agriculture & Technology, Pantnagar, Uttarakhand, India.
    Kisi, Ozgur
    School of Business, Technology and Education, Ilia State University, Tbilisi, Georgia.
    Salih, Sinan Q.
    Institute of Research and Development, Duy Tan University, Da Nang, Vietnam.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Yaseen, Zaher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    The Implementation of a Hybrid Model for Hilly Sub-Watershed Prioritization Using Morphometric Variables: Case Study in India2019Ingår i: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, nr 6, s. 1-19, artikel-id 1138Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Among several components of watershed prioritization, morphometric parameters are considered to be essential elements for appropriate water resource planning and anagement. In the current study, nine hilly sub-watersheds are prioritized using novel hybrid model ased on morphometric variables analysis at Bino Watershed (BW) located in the upper Ramganga basin, India. The proposed model is based on the hybridization of principal component analysis (PCA) with weighted-sum approach (WSA), presenting a single-frame methodology (PCWSA) for sub-watershed prioritization. The prioritization process was conducted based on several morphometric parameters including linear, areal, and shape. The PCA was performed to identify the significant correlated factor-loading matrix whereas WSA was established to provide the weights for the morphometric parameters and fix their priority ranking (PR) to be categorized based on compound factor value. The findings showed that 37.81% of total area is under highly susceptible zone sub-watersheds (SW-6 and SW-7). This is verifying the necessity for appropriate soil and water conservation measures for the area. The proposed hybrid methodology demonstrated a reliable approach for water resource planning and management, agriculture, and irrigation activities in the study region.

  • 240.
    Mohammad, M. E.
    et al.
    Department of Dams and Water Resources Engineering, University of Mosul, Mosul, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Application of SWAT model to estimate the annual runoff and sediment of Duhok reservoir watershed2016Ingår i: Icse 2016 Scour and Erosion Proceedings of the 8th International Conference on Scour and Erosion: Oxford, Uk< 12-15 September 2016 / [ed] Harris, John; Whitehouse, Richard; Moxon, Sarah, London: Taylor & Francis Group, 2016, s. 1129-1136Konferensbidrag (Refereegranskat)
    Abstract [en]

    Estimation of runoff volume and sediment load is a problem that directly affects the performance of dams due to the reduction in the storage capacity of their reservoirs and their effect on dam efficiency and operation schedule. The simulation models can be considered for evaluation of sediment potential if the continuous field measurements are not available. Soil and Water Assessment Tool (SWAT) was applied to estimate the annual runoff volume and sediment load for Duhok Dam Reservoir in north of Duhok/Iraq for the period 1988–2011. The estimated annual runoff volume varied from2.6 to 34.7 MCM. Those values are affected by rainfall depth, intensity and runoff coefficient, while the annual runoff coefficient for the studied area ranged from 0.06 to 0.33 (average is 0.19) causing an average runoff volume of 14.3 MCM. The sediment routing indicated that the values of sediment yields varied from 50 to 1400 t/km2/year depending on sub basin properties. The average annual sediment load from the whole watershed was 124.6 *103 ton. The estimated total sediment arrived to Duhok Reservoir for the considered period 1988–2011 was about 2.99*106 ton.

  • 241.
    Mohammad, Mohammad E.
    et al.
    Department Dams and Water Resources Engineering, University of Mosul.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mining and Geotechnical Engineering - Swedish Blasting Research Centre.
    Issa, Issa E.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sediment in Mosul Dam reservoir using the HEC-RAS model: Sediment in Mosul Dam reservoir using the HEC-RAS model2016Ingår i: Lakes & Reservoirs: Research and Management, ISSN 1320-5331, E-ISSN 1440-1770, Vol. 21, nr 3, s. 235-244Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mosul Dam, located on the Tigris River north of Iraq, is experiencing sedimentation problems, especially near the Al-Jazeera pumping station that supplies the irrigation water for the Al-Jazeera project. The sources of the sediment accumulated within the reservoir are from the Tigris River, as well as ten side valleys on both sides of the reservoir. The sediment inflow rate into the reservoir and the released values are considered on the basis of the operation schedule of the dam for the considered period from 1986 to 2011. The sediment loads were estimated on the basis of available measurements and estimated literature values. The HEC-RAS 4.1 model was used for flows and sediments in the main river and  reservoir. The model was calibrated for flow simulations (coefficient of determination r2 = 0.87) and sediment routing based on bed level, (with resultant r2 = 0.98 and Mean Absolute Deviation of 0.95). The Ackers–White equation was used in the HEC-RAS model for sediment routing because of the wide range of sediment sizes in the study case. The resultant total accumulated sediment load volume was 1.13 km3, a value that is very close to the measured values (1.143 km3) obtained from a previous bathymetric survey. Furthermore, the model indicated most of the sediment (80.7%) was deposited during the first five of the dam operation.

  • 242.
    Mohammad, Mohammad E.
    et al.
    Department of Dams and Water Resources Engineering, University of Mosul.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Annual Runoff and Sediment in Duhok Reservoir Watershed Using SWAT and WEPP Models2016Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 7, s. 410-422Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Estimation of runoff volume and sediment load is the main problem that affects the performance of dams due to the reduction in the storage capacity of their reservoirs and their effect on dam efficiency and operation schedule. The simulation models can be considered for this purpose if the continuous field measurements are not available. Soil and Water Assessment Tool (SWAT) andWater Erosion Prediction Project (WEPP) models were applied to estimate the annual runoff volume and sediment load for Duhok Dam Reservoir in north of Duhok/Iraq for the period 1988-2011. The estimated annual runoff volume varied from 2.3 to 34.7 MCM for considered period.Those values were affected by rainfall depth, intensity and runoff coefficient. The resultant annual runoff coefficient for the studied area ranged from 0.05 to 0.35 (average was 0.18) causing an average runoff volume of about 14 MCM. The results of sediment routing indicated that the values of sediment yields varied from 50 to 1400 t/km2/year depending on sub basin properties. The average annual sediment load from the whole watershed is about 120 × 103 ton. The estimated total sediment arrived to Duhok Reservoir for the considered period 1988-2011 was about 2.9 × 106 ton. The results indicate that both models gave reasonable results in comparison with measured values. Based on statistical criteria, the results of both models are close to gather.

  • 243.
    Naganna, Sujay Raghavendra
    et al.
    Department of Civil Engineering, Shri Madhwa Vadiraja Institute of Technology and Management, Bantakal, Udupi, India. Visvesvaraya Technological University, Belagavi, Karnataka, India.
    Deka, Paresh Chandra
    Department of Applied Mechanics and Hydraulics, National Institute of Technology Karnataka, Surathkal, Mangalore, India.
    Ghorbani, Mohammad Ali
    Department of Civil Engineering, Near East University, Nicosia, Turkey. Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.
    Biazar, Seyed Mostafa
    Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Yaseen, Zaher Mundher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Dew Point Temperature Estimation: Application of Artificial Intelligence Model Integrated with Nature-Inspired Optimization Algorithms2019Ingår i: Water, ISSN 2073-4441, E-ISSN 2073-4441, water, Vol. 11, nr 4, artikel-id 742Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dew point temperature (DPT) is known to fluctuate in space and time regardless of the climatic zone considered. The accurate estimation of the DPT is highly significant for various applications of hydro and agro–climatological researches. The current research investigated the hybridization of a multilayer perceptron (MLP) neural network with nature-inspired optimization algorithms (i.e., gravitational search (GSA) and firefly (FFA)) to model the DPT of two climatically contrasted (humid and semi-arid) regions in India. Daily time scale measured weather information, such as wet bulb temperature (WBT), vapor pressure (VP), relative humidity (RH), and dew point temperature, was used to build the proposed predictive models. The efficiencies of the proposed hybrid MLP networks (MLP–FFA and MLP–GSA) were authenticated against standard MLP tuned by a Levenberg–Marquardt back-propagation algorithm, extreme learning machine (ELM), and support vector machine (SVM) models. Statistical evaluation metrics such as Nash Sutcliffe efficiency (NSE), root mean square error (RMSE), and mean absolute error (MAE) were used to validate the model efficiency. The proposed hybrid MLP models exhibited excellent estimation accuracy. The hybridization of MLP with nature-inspired optimization algorithms boosted the estimation accuracy that is clearly owing to the tuning robustness. In general, the applied methodology showed very convincing results for both inspected climate zones.

  • 244.
    Naji, Laith A.
    et al.
    Department of Environmental Engineering, College of Engineering, University of Baghdad, Iraq.
    Jassam, Salim H.
    Department of Building and Construction Technology Engineering, Technical College Baghdad, Middle Technical University.
    Yaseen, Mohammed J.
    Department of Environmental Engineering, Mustansiriayah University, Baghdad, Iraq.
    Faisal, Ayad A. H.
    Department of Environmental Engineering, College of Engineering, University of Baghdad, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Modification of Langmuir model for simulating initial pH and temperature effects on sorption process2019Ingår i: Separation science and technology (Print), ISSN 0149-6395, E-ISSN 1520-5754Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The present study modifies the sorption isothermfor simulating the influences of initial pH and temperature variations on thecadmium sorption from contaminated water using waste foundry sand based on Langmuir,Freundlich and Temkin models. Results proved that the Langmuir expression is ableto adopt these effects by relating sorption capacity and affinity constantswith pH and temperature of aqueous solution through exponential relationships (determinationcoefficient = 0.9375). The present model is assumed that the sorption process occursthrough acidic functional groups and this is consistent with FTIR outputs. Interactionof cadmium/WFS is found to be exothermic by thermodynamic analysis.

  • 245.
    Nasrin Baby, Sultana
    et al.
    School of Mathematical and Geospatial Sciences, Royal Melbourne Institute of Technology, Australia.
    Arrowsmith, Colin
    School of Mathematical and Geospatial Sciences, Royal Melbourne Institute of Technology, Australia.
    Abbas, Nahla
    School of Engineering and Technology, Central Queensland, University, Australia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Climate Change Impacts on Water Resources of AryCreek, Inverloch, Victoria2018Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 12, nr 10, s. 727-740Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Understanding urban wetland ecosystem services structure allows managers to base restoration efforts on multiple user end-benefits. Ary Creek can provide the coupled function of improving water quality and mitigating floods through delayed stormwater flow. It is fundamental to identify areas surrounded by water for the safety of individual should in case the water level raise beyond areasonable doubt and might cause a flood. For many years, the Ary Creek catchment in Inverloch has been flooding and causing great problems for the inhabitants as well as the environment. The procedure is to develop models of the area around the catchment or watershed using Victorian Coastal LiDAR and other input data from the GIS (geographic information system). This study uses the real-time simulation in ArcSWAT—ArcGIS 10.3 and 3D in ArcScene 10.3, and the variables obtained from the soil and water assessment tool ArcSWAT such as the land use, soil and slope are the parameters measured to induce the flood. When certain portions of the Hydrologic response unit HRU, land use, soil or slope is changed due to temporal adjustment and climate change, then the model can predict zones of low, moderate and high flood risk. The 3D simulations appear to produce a visual model for decision-making, planning, management, and mitigation. The simulation helps in determining the extent of the flood by using animation.

  • 246.
    O. Abdullah, Twana
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi. Groundwater Directorate of Sulaimani, Kurdistan Region, Iraq.
    S. Ali, Salahalddin
    Department of Geology, University of Sulaimani, Kurdistan Region, Iraq;Komar University of Science and Technology, Sulaimani, Iraqi Kurdistan Region, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment of Groundwater Vulnerability to Pollution Using VLDA and COP Models in Halabja Saidsadiq Basin, Iraq2018Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 12, nr 11, s. 798-809, artikel-id 003Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Groundwater aquifer in the Halabja and Saidsadiq Basin considered being one of the most important aquifers in terms of water supplying in Kurdistan Region, NE of Iraq. The growing of economics, irrigation and agricultural activities inside the basin makes it of the main essentials to the region. Therefore, pollution of groundwater is of specific worry as groundwater resources are the principal source of water for drinking, agriculture, irrigation and industrial activities. Thus, the best and practical arrangement is to keep the pollution of groundwater through. The current study aims the evaluation of the vulnerability of groundwater aquifers of the study area. Two models were applied, to be specific VLDA and COP to develop maps of groundwater vulnerability for contamination. The VLDA model classified the area into four classes of vulnerability with each covered area: low (2%), moderate (44%), high (53%) and very high (1%). While four vulnerability classes were accomplished dependent on COP model including very low, low, moderate and high vulnerability classes with coverage areas of (1%, 37%, 2% and 60%) respectively. To confirm the suitability of each map for assessment of groundwater vulnerability in the area, it required to be validated of the theoretical sympathetic of current hydrogeological conditions. In this study, groundwater age evaluated utilizing tritium isotopes investigation and applied it to validate the vulnerability results. Based on this validation, the outcome exhibits that the vulnerability classes acquired utilizing VLDA model are more predictable contrasted with the COP model.

  • 247.
    Osman, Yasin
    et al.
    University of Bolton.
    Abdellatif, Mawada
    Liverpool JM University.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jawad, Sadeq
    Iraqi Government, Prime Minister Advisory Commission.
    Climate Change and Future Precipitation in Arid Environment of Middle East: Case study of Iraq2017Ingår i: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 25, s. 1-18, artikel-id 3Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper impact of climate change on precipitation in the arid environment of Iraq is examined.  LARS-WG weather generator was applied to 5 representative regions to model current and future precipitation under climate change. Seven Global Climate Models (GCMs) have been employed to account for any uncertainty on future projection for three selected periods, 2011-2030, 2046-2065 and 2080-2099. Performance of LARS-WG in each site was first evaluated using the Kolmogorov-Smirnov statistical test for fitting wet/dry days in each site, as well as comparison of the mean and standard deviation between the observed and simulated precipitation. The developed LARS-WG models were found to perform well and skilful in simulating precipitation in the arid regions of Iraq as evidenced by the tests carried and the comparison made. The precipitation models were then used to obtain future projections for precipitation using the IPCC scenario SRES A2. Future precipitation results show that most of the Iraq regions are projected to suffer a reduction in annual mean precipitation, especially by the end of the 21st century, while on a seasonal basis most of the regions are anticipated to be wetter in autumn and winter.

     

  • 248.
    Osman, Yasin
    et al.
    Faculty of Advanced Engineering and Sciences, University of Bolton.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Abdellatif, Mawada
    Faculty of Engineering and Technology, Liverpool JM University .
    Climate change model as a decision support tool for water resources management in northern Iraq: a case studyof Greater Zab River2017Ingår i: Journal of Water and Climate, ISSN 2040-2244, Vol. 8, nr 4, s. 197-209Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The northern region of Iraq heavily depends on rivers, such as the Greater Zab, for water supply and irrigation. Thus, river water management in light of future climate change is of paramount importance in the region. In this study, daily rainfall and temperature obtained from the Greater Zab catchment, for 1961 –2008, were used in building rainfall and evapotranspiration models using LARSWG and multiple linear regressions, respectively. A rainfall –runoff model, in the form of autoregressive model with exogenous factors, has been developed using observed flow, rainfall and evapotranspiration data. The calibrated rainfall

    –runoff model was subsequently used to investigate the impacts of climate change on the Greater Zab flows for the near (2011–2030), medium (2046–2065), and far (2080–2099) futures. Results from the impacts model showed that the catchment is projected to suffer a significant reduction in total annual flow in the far future; with more severe drop during the winter and spring seasons in the range of 25 to 65%. This would have serious ramifications for the current agricultural activities in the catchment. The results could be of significant benefits for water management planners in the catchment as they can be used in allocating water for different users in the catchment.

  • 249. Osman, Yassin
    et al.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Adbellatif, Mawada
    Al-Jawad, Sadeq
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Expected Future Precipitation in Central Iraq Using LARS-WG Stochastic Weather Generator2014Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 6, nr 13, s. 948-959Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Middle East (ME) is characterized by its water shortage problem. This region with its arid climate is expected to be the most vulnerable in the world to the potential impacts of climate change. Iraq (located in ME) is seriously experiencing water shortage problem. To overcome this problem rain water harvesting can be used. In this study the applicability of the long-term weather generator model in downscaling daily precipitation Central Iraq is used to project future changes of precipitation based on scenario of seven General Circulation Models (GCMs) outputs for the periods of 2011-2030, 2046-2065, and 2080-2099. The results indicated that December-February and September-November periods, based on the ensemble mean of seven GCMs, showed an increasing trend in the periods considered; however, a decreasing trend can be found in March, April, and May in the future.

  • 250.
    Pusch, Roland
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Kasbohm, Jörn
    Institute of Geography and Geology, Ernst-Moritz-Arndt-University of Greifswald, University of Greifswald, GeoENcon Ltd.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Yang, Ting
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Knutsson, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Comparison of two genuinely geological alternatives for disposal of highly radioactive waste (HLW)2016Ingår i: Comunicações Geológicas, ISSN 0873-948X, E-ISSN 1647-581XArtikel i tidskrift (Refereegranskat)
    Abstract [en]

    Disposal of highly radioactive waste (HLW) can be environmentally acceptable if radionuclides are kept isolated from the groundwater, which has inspired planners of repositories to work out multibarrier concepts that postulate defined functions of the host rock and engineered waste confinements. Assessment of the role of the host rock involves groundwater flow modelling and rock mechanical analysis, which are both highly speculative and ignore future changes in rock structure, stress conditions, and groundwater flow. Widening the perspective by considering the integrated physical performance of interacting geological strata respecting groundwater flow conditions can provide excellent isolation of HLW with a minimum of engineered barriers as illustrated by the principle of very deep boreholes (VDH) for which the very high salt content of deep water is the primary barrier by maintaining possibly contaminated groundwater at depth. Such isolation of groundwater regimes can also be obtained by constructing repositories in crystalline rock covered by clay-containing sedimentary rock in regions with no or very low hydraulic gradients, particularly if the two principles are combined. The paper describes a possible case of this type, showing that effective isolation of HLW in repositories of commonly discussed types, KBS-3H and VDH, can be achieved under present and foreseeable climatic conditions. The paper compares the short- and long-term functions of repositories located at the southern end of the Swedish island Gotland, being an example of desired geological conditions that are found also in other parts of Sweden and in Lithuania, Germany, Holland and the UK. Here, 500 m of sediment rock series cover gneiss bedrock in which a KBS-3H repository of SKB-type can be built under virtually “dry” conditions because of the tightness of the overlying sedimentary rock and lack of hydraulic gradients in the crystalline rock. Shafts leading down from the ground surface to the repository level are constructed by use of freezing technique and lined with low-pH concrete before installation of waste after which they have to be sealed with expanding clay. Use of initially largely water-saturated clay provides suitable physical properties of the embedment of waste containers. Alternatively, a VDH repository consisting of a number of steep 4 km deep boreholes with about 800 mm diameter can be driven for installing waste below 2 km depth, leaving the upper 2 km for sealing with clay. The geological conditions, which are also believed to provide acceptable rock pressure conditions for construction of a KBS-3H repository at about 600 m depth, are believed to be suitable for the construction and short- and long-term performance of either repository type.

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