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  • 1.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Groundwater Directorate of Sulaimani, Kurdistan,Iraq.
    Ali, Salahalddin S.
    Department of Geology, University of Sulaimani,Kurdistan, Iraq. Komar University of Science and Technology, Iraqi Kurdistan , Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Hydrogeochemical Evaluation of Groundwater and Its Suitability for Domestic Uses in Halabja Saidsadiq Basin, Iraq2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 4, article id 690Article in journal (Refereed)
    Abstract [en]

    Evaluation of the hydrogeochemical characteristics and groundwater suitability for

    domestic use was conducted in the Halabja Saidsadiq Basin in the northeastern part of Iraq. The total studied area is about 1278 km 2 with a specific Mediterranean-type continental interior climate, which is cold in winter and hot in summer. To conduct the required laboratory chemical analysis for groundwater samples in the studied basin, 78 groundwater samples, in total, were collected from 39 water wells in the dry and wet seasons in 2014 and analyzed for major cations and anions, and the results were compared with the permitted limits for drinking water. An examination of the chemical concentrations of the World Health Organization drinking water norms demonstrate that a large portion of the groundwater samples is suitable for drinking, and a preponderance of groundwater samples situated in the class of hard and very hard water types for both seasons. Suitability of groundwater for drinking use was additionally assessed according to the water quality index classification. This showed that more than 98% of groundwater samples have good water quality in the dry and wet seasons. Conversely, the classification of groundwater samples based on Piper’s diagram designates that the groundwater type is alkaline water, with existing bicarbonate

    along with sulfate and chloride. However, water–ock exchange processes and groundwater flow have been responsible for the dominant water type of Ca–g–CO3.

  • 2.
    Al-Madhlom, Qais
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. College of Engineering/Al-Musaib, University of Babylon, Hillah, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Laue, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hussain, Hussain Musa
    Remote Sensing Center, University of Kufa, Kufa, Iraq.
    Site Selection of Aquifer Thermal Energy Storage Systems in Shallow Groundwater Conditions2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 7, article id 1393Article in journal (Refereed)
    Abstract [en]

    Underground thermal energy storage (UTES) systems are widely used around the world, due

    to their relations to heating ventilating and air conditioning (HVAC) applications [1]. To achieve the required objectives of these systems, the best design of these systems should be accessed first. The process of determining the best design for any UTES system has two stages, the type selection stage and the site selection stage. In the type selection stage, the best sort of UTES system is determined. There are six kinds of UTES systems, they are: boreholes, aquifer, bit, tank, tubes in clay, and cavern [2–5]. The selection of a particular type depends on three groups of parameters. They are: Site specific, design, and operation parameters (Figure 1). Apart from site specific parameters, the other two types can be changed through the life time of the system. The site specific parameters, e.g., geological,

    hydrogeological, and metrological, cannot be changed during the service period of the  ystem. Therefore, the design of the best type should depend, at first consideration, on site specific parameters.

  • 3.
    Ameen, Ameen Mohammed Salih
    et al.
    Department of Civil Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur .
    Ibrahim, Zainah
    Department of Civil Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur .
    Othman, Faridah
    Department of Civil Engineering, Faculty of Engineering, University Malaya, Kuala Lumpur .
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Yaseen, Zaher Mundher
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Minimizing the Principle Stresses of Powerhoused Rock-Fill Dams Using Control Turbine Running Units: Application of Finite Element Method2018In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 10, no 9, article id 1138Article in journal (Refereed)
    Abstract [en]

    This study focuses on improving the safety of embankment dams by considering theeffects of vibration due to powerhouse operation on the dam body. The study contains two ainparts. In the first part, ANSYS-CFX is used to create the three-dimensional (3D) Finite Volume (FV)model of one vertical Francis turbine unit. The 3D model is run by considering various reservoirconditions and the dimensions of units. The Re-Normalization Group (RNG) k-𝜀𝜀 turbulence modelis employed, and the physical properties of water and the flow haracteristics are defined in theturbine model. In the second phases, a 3D finite element (FE) numerical model for a rock-fill dam iscreated by using ANSYS®, considering the dam connection with its powerhouse represented by fourvertical Francis turbines, foundation, and the upstream reservoir. Changing the upstream watertable minimum and maximum water levels, standers earth gravity, fluid-solid interface, hydrostaticpressure, and the soil properties are onsidered. The dam model runs to cover all possibilities forturbines operating in accordance with the reservoir discharge ranges. In order to minimize stressesin the dam body and increase dam safety, this study optimizes the turbine operating system byintegrating turbine and dam models.

  • 4.
    Andersson, Robin
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Hellström, J. Gunnar I.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Andreasson, Patrik
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics. Vattenfall AB Research and Development, Älvkarleby Laboratory, Älvkarleby.
    Lundström, Staffan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Numerical investigation of a hydropower tunnel: Estimating localised head-loss using the manning equation2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, no 8, article id 1562Article in journal (Refereed)
    Abstract [en]

    The fluid dynamics within a water tunnel is investigated numerically using a RANS approach with the k-ε turbulence model. The computational model is based on a laser scan of a hydropower tunnel located in Gävunda, Sweden. The tunnel has a typical height of 6.9 m and a width of 7.2 m. While the average cross-sectional shape of the tunnel is smooth the local deviations are significant, where some roughness elements may be in the size of 5 m implying a large variation of the hydraulic radius. The results indicate that the Manning equation can successfully be used to study the localised pressure variations by taking into account the varying hydraulic radius and cross-sectional area of the tunnel. This indicates a dominant effect of the tunnel roughness in connection with the flow, which has the potential to be used in the future evaluation of tunnel durability. ANSYS-CFX was used for the simulations along with ICEM-CFD for building the mesh. 

  • 5.
    Bin Asad, S M Sayeed
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Lundström, Staffan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Andersson, Anders G.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Hellström, J. Gunnar I.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Leonardsson, Kjell
    Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Wall shear stress measurement on curve objects with PIV in connection to benthic fauna in regulated rivers2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 4, article id 650Article in journal (Refereed)
    Abstract [en]

    The flow characteristics in the vicinity of a set of half-cylinders of different sizes simulating benthic objects were studied experimentally using particle image velocimetry (PIV). The cylinders were mounted on the bottom of an open channel, and the influence of the flow speed on the distribution of the shear stress along the bottom geometry was investigated. Of special interest was how the shear stress changes close to the wall as a function of the flow speed and cylinder arrangement. It was found that the shear stress varies significantly as a function of position. This implies habitat heterogeneity allowing benthic invertebrates with different shear stress tolerance exists when the bottom consists of differently sized stones. It was also shown that direct measurements of near wall velocity gradients are necessary to accurately calculate the wall shear stress for more complex geometries.

  • 6.
    Driessen, Peter P. J.
    et al.
    Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, The Netherlands.
    Hegger, Dries L.T.
    Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, The Netherlands.
    Kundzewicz, Zbigniew W.
    Institute for Agricultural and Forest Environment, Polish Academy of Sciences, Poznań, Poland. Potsdam Institute for Climate Impact Research, Potsdam, Germany.
    van Rijswick, Helena F. M. W.
    Utrecht Centre for Water, Oceans and Sustainability Law, Utrecht University School of Law, Utrecht, The Netherlands.
    Crabbé, Ann
    Research Group Environment & Society, Sociology Department, Faculty of Social Sciences, University of Antwerp, Antwerp, Belgium.
    Larrue, Corinne
    Paris School of Planning, Lab’Urba, Paris Est University, Marne La Vallée, France.
    Matczak, Piotr
    Institute of Sociology, Adam Mickiewicz University, Poznań, Poland.
    Pettersson, Maria
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Priest, Sally
    Flood Hazard Research Centre, Middlesex University, London, UK.
    Suykens, Cathy
    Utrecht Centre for Water, Oceans and Sustainability Law, Utrecht University School of Law, Utrecht, The Netherlands. Institute for Environmental and Energy Law, KU Leuven, Leuven, Belgium.
    Raadgever, Gerrit Thomas
    Sweco Netherlands, The Netherlands.
    Wiering, Mark
    Institute for Management Research, Radboud University Nijmegen, Nijmegen, The Netherlands.
    Governance Strategies for Improving Flood Resilience in the Face of Climate Change2018In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 10, no 11, article id 1595Article in journal (Refereed)
    Abstract [en]

    Flooding is the most common of all natural disasters and accounts for large numbers of casualties and a high amount of economic damage worldwide. To be ‘flood resilient’, countries should have sufficient capacity to resist, the capacity to absorb and recover, and the capacity to transform and adapt. Based on international comparative research, we conclude that six key governance strategies will enhance ‘flood resilience’ and will secure the necessary capacities. These strategies pertain to: (i) the diversification of flood risk management approaches; (ii) the alignment of flood risk management approaches to overcome fragmentation; (iii) the involvement, cooperation, and alignment of both public and private actors in flood risk management; (iv) the presence of adequate formal rules that balance legal certainty and flexibility; (v) the assurance of sufficient financial and other types of resources; (vi) the adoption of normative principles that adequately deal with distributional effects. These governance strategies appear to be relevant across different physical and institutional contexts. The findings may also hold valuable lessons for the governance of climate adaptation more generally.

  • 7.
    Ewaid, Salam Hussein
    et al.
    Technical Institute of Shatra, Southern Technical University, Diwaniyah, Iraq.
    Abed, Salwan Ali
    Department of Environment, College of Science, University of Al Qadisiyah, Al-Qadisiyah, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Crop Water Requirements and Irrigation Schedules for Some Major Crops in Southern Iraq2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 4, article id 756Article in journal (Refereed)
    Abstract [en]

    The climate of Iraq is of the subtropical semi-dry type; however, the country was rich in water resources until a few decades ago. Climate change and the construction of many dams on the Tigris and Euphrates rivers in the neighboring countries have caused water shortages and poor water quality. Now, there is a need to decrease consumption, improve management of water resources, and determine the water requirements of the major crops because agriculture is the first consumer of water in Iraq. The Food and Agriculture Organization (FAO) CROPWAT 8.0 simulation software and the CLIMWAT 2.0 tool attached to it have been used in this research for Dhi-Qar Province in southern Iraq to find the crop water requirements (CWRs) and irrigation schedules for some major crops. The CROPWAT Penman–Monteith method was used to calculate the reference crop evapotranspiration (ET0) and the United States Department of Agriculture (USDA) soil conservation (S.C.) method was used to estimate the effective rainfall. The study results showed that ET0 varied from 2.18 to 10.5 mm/day and the effective rainfall varied from 0.0 to 23.1 mm. The irrigation requirements were 1142, 203.2, 844.8, and 1180 mm/dec for wheat, barley, white corn, and tomatoes, respectively. There is a higher water demand for crops during the dry seasons (summer and autumn) and a lower demand during the wet seasons (winter and spring). The total gross irrigation and the total net irrigation were 343.8 mm and 240.7 mm for wheat, 175.2 mm and 122.6 mm for barley, 343.8 mm and 240.7 mm for white corn, and 203.3 mm and 142.3 mm for tomatoes. This study proved that the CROPWAT model is useful for calculating the crop irrigation needs for the proper management of water resources.

  • 8.
    Ewaid, Salam Hussein
    et al.
    Technical Institute of Shatra, Southern Technical University, Al-Qadisiyah, Iraq.
    Abed, Salwan Ali
    Department of Environment, College of Science, University of Al-Qadisiyah, Al-Qadisiyah, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Water Footprint of Wheat in Iraq2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 3, article id 535Article in journal (Refereed)
    Abstract [en]

    The water footprint (WF) is an indicator of indirect and direct fresh water use. In respect of

    facilitating decision-making processes,WF gives an excellent perspective on how and where fresh water is used in the supply chain. More than 39million people live in Iraq and,with a growing population, there is a water shortage and a rising demand for food that cannot be met in the future. In this study, theWF of wheat production is estimated for the year 2016–2017 for 15 Iraqi provinces. TheWF was calculated using the method ofMekonnen and Hoekstra (2011) and the CROPWAT and CLIMWAT softwares’ crop water requirement option. It was found that theWF in m 3/ton was 1876 m3/ton. The 15 provinces showed variations inWFs, which can be ascribed to the difference in climate and production values. The highest

    wheat WF was found in Nineveh province, followed by Muthanna, Anbar, and Basra. The last three provinces produce little and have a highWF so, in these provinces, wheat can be replaced with crops that need less water and provide more economic benefit. There is an opportunity to reduce the greenWF by increasing production from the 4 rain-fed provinces, which will reduce the need for production from the irrigated provinces and, therefore, reduce the use of blue water.

  • 9.
    Ezz-Aldeen, Mohammad
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Hassan, Rebwar
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Ammar
    Department of Water Resources Engineering, Baghdad Universi.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Watershed Sediment and Its Effect on Storage Capacity: Case Study of Dokan Dam Reservoir2018In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 10, no 7, article id 858Article in journal (Refereed)
    Abstract [en]

    Dokan is a multipurpose dam located on the Lesser Zab River in the Iraq/Kurdistan region. The dam has operated since 1959, and it drains an area of 11,690 km2. All reservoirs in the world suffer from sediment deposition. It is one of the main problems for reservoir life sustainability. Sustainable reservoir sediment-management practices enable the reservoir to function for a longer period of time by reducing reservoir sedimentation. This study aims to assess the annual runoff and sediment loads of the Dokan Dam watershed using the soil and water assessment tool (SWAT) model to evaluate the relative contributions in comparison with the total values delivered from both watershed and Lesser Zab River and to identify the basins with a high sediment load per unit area. These help in the process of developing a plan and strategy to manage sediment inflow and deposition. The SUFI-2 program was applied for a model calibrated based on the available field measurements of the adjacent Derbendekhan Dam watershed, which has similar geological formations, characteristics and weather. For the calibration period (1961–1968), the considered statistical criteria of determination coefficients and Nash–Sutcliffe model efficiency were 0.75 and 0.64 for runoff while the coefficients were 0.65 and 0.63 for sediment load, respectively. The regionalization technique for parameter transformation from Derbendekhan to Dokan watershed was applied. Furthermore, the model was validated based on transformed parameters and the available observed flow at the Dokan watershed for the period (1961–1964); they gave reasonable results for the determination coefficients and Nash–Sutcliffe model efficiency, which were 0.68 and 0.64, respectively. The results of SWAT project simulation for Dokan watershed for the period (1959–2014) indicated that the average annual runoff volume which entered the reservoir was about 2100 million cubic meters (MCM). The total sediment delivered to the reservoir was about 72 MCM over the 56 years of dam life, which is equivalent to 10% of the reservoir dead storage. Two regression formulas were presented to correlate the annual runoff volume and sediment load with annual rain depth for the studied area. In addition, a spatial distribution of average annual sediment load was constructed to identify the sub basin of the high contribution of sediment load.

  • 10.
    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 University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    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 Study2018In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 10, no 1270, p. 2-20Article in journal (Refereed)
    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.

  • 11.
    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 University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    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 India2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 6, p. 1-19, article id 1138Article in journal (Refereed)
    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.

  • 12.
    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 University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    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 Algorithms2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, water, Vol. 11, no 4, article id 742Article in journal (Refereed)
    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.

  • 13.
    Panasiuk, Oleksandr
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Langeveld, Jeroen
    Department of Water Management, TU Delft. Partners4UrbanWater, The Netherlands.
    de Haan, Cornelis
    Partners4UrbanWater, The Netherlands.
    Liefting, Erik
    Partners4UrbanWater, The Netherlands.
    Schilperoort, Remy
    Partners4UrbanWater, The Netherlands.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Using Distributed Temperature Sensing (DTS) for Locating and Characterising Infiltration and Inflow into Foul Sewers before, during and after Snowmelt Period2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 8, article id 1529Article in journal (Refereed)
    Abstract [en]

    Infiltration and inflow (I/I) into sewers cause negative effects on the sewer system,wastewater treatment plant and environment. Identifying the causes and locating the inflows isnecessary in order to address the I/I problem. This paper focuses on using distributed temperaturesensing (DTS) for identifying, locating and characterising I/I into a sewer system during the endof winter–beginning of summer transition period under dry and wet weather conditions. Duringsnowmelt, several locations with I/I were identified, while these locations did not show I/I duringstorm events after the snowmelt. In addition, during a very heavy storm after the snowmelt period,I/I was found at other locations. Therefore, DTS was demonstrated to be effective in identifying thetype of I/I and in locating I/I. Finally, I/I monitoring campaigns in cold climates should take intoaccount the variety of pathways of I/I during snowmelt and during rainfall.

  • 14.
    Qutbudin, Ishanch
    et al.
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Shiru, Mohammed Sanusi
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia. Department of Environmental Sciences, Faculty of Science, Federal University Dutse, Dutse, Nigeria.
    Sharafati, Ahmad
    Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran.
    Ahmed, Kamal
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia. Faculty of Water Resource Management, Lasbela University of Agriculture, Water and Marine Sciences, Balochistan, Pakistan.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    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
    Department of Water and Environmental Engineering, School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Malaysia.
    Wang, Xiaojun
    State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing, China. Research Center for Climate Change, Ministry of Water Resources, Nanjing, China.
    Seasonal Drought Pattern Changes Due to Climate Variability: Case Study in Afghanistan2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 5, p. 1-20, article id 1096Article in journal (Refereed)
    Abstract [en]

    We assessed the changes in meteorological drought severity and drought return periods during cropping seasons in Afghanistan for the period of 1901 to 2010. The droughts in the country were analyzed using the standardized precipitation evapotranspiration index (SPEI). Global Precipitation Climatology Center rainfall and Climate Research Unit temperature data both at 0.5 resolutions were used for this purpose. Seasonal drought return periods were estimated using the values of the SPEI fitted with the best distribution function. Trends in climatic variables and SPEI were assessed using modified Mann–Kendal trend test, which has the ability to remove the influence of long-term persistence on trend significance. The study revealed increases in drought severity and frequency in Afghanistan over the study period. Temperature, which increased up to 0.14 C/decade, was the major factor influencing the decreasing trend in the SPEI values in the northwest and southwest of the country during rice- and corn-growing seasons, whereas increasing temperature and decreasing rainfall were the cause of a decrease in SPEI during wheat-growing season. We concluded that temperature plays a more significant role in decreasing the SPEI values and, therefore, more severe droughts in the future are expected due to global warming.

  • 15.
    Tayebiyan, Aida
    et al.
    Kerman University of Medical Sciences, Kerman, Iran.
    Mohammad, Thamer Ahmad
    University of Baghdad, Jadriya, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Malakootian, Mohammad
    Kerman University of Medical Sciences, Kerman, Iran.
    Comparison of Optimal Hedging Policies forHydropower Reservoir System Operation2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 1, article id 121Article in journal (Refereed)
    Abstract [en]

    Reservoiroperation rules play an important role in regions economic development.Meanwhile, hedging policies are mostly applied for municipal, industrial, andirrigation water supplies from reservoirs and it is less used for reservoiroperation for hydropower generation. The concept of hedging and rationingfactors can be used to maintain the water in a reservoir for the sake ofincreasing water storage and water head for future use. However, water storageand head are the key factors in operation of reservoir systems for hydropowergeneration. This study investigates the applicability of seven competinghedging policies including four customary forms of hedging (1PHP, 2PHP, 3PHP,DHP) and three new forms of hedging rules (SOPHP, BSOPHP, SHPHP) for reservoiroperation for hydropower generation. The models were constructed in MATLABR2011b based on the characteristics of the Batang Padang hydropower reservoirsystem, Malaysia. In order to maximize the output of power generation inoperational periods (2003–2009), threeoptimization algorithms namely particle swarm optimization (PSO), geneticalgorithm (GA), and hybrid PSO-GA were linked to one of the constructed model(1PHP as a test) to find the most effective algorithm. Since the results demonstrated the superiority of the hybrid PSO-GA algorithm compared to either PSO or GA, the hybrid PSO-GA were linkedto each constructed model in order to find the optimal decision variables of eachmodel. The proposed methodology was validated using monthly data from 2010–2012.The results showed that there are no significant difference between the output of monthly meanpower generation during 2003–2009 and 2010–2012.The results declared that by applying the proposedpolicies, the output of power generation could increase by 13% with respect tothe historical management. Moreover, the discrepancies between mean powergenerations from highest to lowest months were reduced from 49 MW to 26 MW,which is almost half. This means that hedging policies could efficientlydistribute the water-supply and power-supply in the operational period andincrease the stability of the system. Among the studied hedging policies, SHPHPis the most convenient policy for hydropower reservoir operation and gave thebest result.

  • 16.
    Xie, Qiancheng
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Yang, J.
    Division of Resources, Energy and Infrastructure, Royal Institute of Technology (KTH), Stockholm, Sweden; Vattenfall AB, Research and Development (R and D), Älvkarleby Laboratory, Älvkarleby, Sweden.
    Lundström, Staffan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Dai, W.
    College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, China.
    Understanding morphodynamic changes of a tidal river confluence through field measurements and numerical modeling2018In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 10, no 10, article id 1424Article in journal (Refereed)
    Abstract [en]

    A confluence is a natural component in river and channel networks. This study deals, through field and numerical studies, with alluvial behaviors of a confluence affected by both river run-offand strong tides. Field measurements were conducted along the rivers including the confluence. Field data show that the changes in flow velocity and sediment concentration are not always in phase with each other. The concentration shows a general trend of decrease from the river mouth to the confluence. For a given location, the tides affect both the sediment concentration and transport. A two-dimensional hydrodynamic model of suspended load was set up to illustrate the combined effects of run-offand tidal flows. Modeled cases included the flood and ebb tides in a wet season. Typical features examined included tidal flow fields, bed shear stress, and scour evolution in the confluence. The confluence migration pattern of scour is dependent on the interaction between the river currents and tidal flows. The flood tides are attributable to the suspended load deposition in the confluence, while the ebb tides in combination with run-offs lead to erosion. The flood tides play a dominant role in the morphodynamic changes of the confluence. 

  • 17.
    Yang, James
    et al.
    Vattenfall AB Research and Development, Älvkarleby Laboratory.
    Andreasson, Patrik
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics. Vattenfall AB Research and Development, Älvkarleby Laboratory.
    Högström, Carl-Maikel
    Vattenfall AB Research and Development, Älvkarleby Laboratory.
    Teng, Penghua
    Division of Resources, Energy and Infrastructure, Royal Institute of Technology.
    The tale of an intake vortex and its mitigation countermeasure: A case study from akkats hydropower station2018In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 10, no 7, article id 881Article in journal (Refereed)
    Abstract [en]

    The upgrade of Akkats power station in Sweden included a new, separate waterway for the addition of a 75 MW generating unit. The vertical intake of its headrace was formed by means of lake tapping. A physical model was used to help understand the blasting process involving fragmented rock, water, air, and gas. Upon commissioning of the unit, swirling flows occurred unexpectedly at the intake, which gave rise to negative consequences including limitations in power output. Echo-sounding showed that the blasted piercing resulted in an irregular intake. A hydraulic model, as part of the design process, was built to examine potential countermeasures for vortex suppression. The final solution was a segmented barrier between the intake and the dam. It effectively suppressed the intake flow circulations; only minor intermittent vortices were left. The fabricated steel segments were anchored into the bedrock, stretching to 1.0 m below the lowest legal reservoir level. The local intake headloss was also reduced. The implemented solution was tested under full turbine loading and the result was satisfactory. Even during winter seasons with ice cover above the wall, the power station ran normally. The case study is expected to provide guidance for solving similar problems with vortex formation.

  • 18.
    Yaseen, Zaher
    et al.
    School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia.
    Ebtehaj, Isa
    Department of Civil Engineering, Razi University, Iran.
    Kim, Sungwon
    Department of Railroad Construction and Safety Engineering, Dongyang University, Korea.
    Sanikhani, Hadi
    Water Engineering Department, Agriculture Faculty, University of Kurdistan, Iran.
    Asadi, H.
    Water Engineering Department, Faculty of Agriculture, University of Tabriz, Iran.
    Ghareb, Mazen Ismaeel
    Department of Computer Science, College of Science and Technology, University of Human Development, Iraq.
    Bonakdari, Hossein
    Department of Civil Engineering, Razi University, Iran.
    Mohtar, Wan Hanna Melini Wan
    Sustainable and Smart Township Research Centre (SUTRA), Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Shahid, Shamsuddin
    School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia.
    Novel Hybrid Data-Intelligence Model for Forecasting Monthly Rainfall with Uncertainty Analysis2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 3, article id 502Article in journal (Refereed)
    Abstract [en]

    In this research, three different evolutionary algorithms (EAs), namely, particle swarm optimization (PSO), genetic algorithm (GA) and differential evolution (DE), are integrated with the adaptive neuro-fuzzy inference system (ANFIS) model. The developed hybrid models are proposed to forecast rainfall time series. The capability of the proposed evolutionary hybrid ANFIS was compared with the conventional ANFIS in forecasting monthly rainfall for the Pahang watershed, Malaysia. To select the optimal model, sixteen different combinations of six different lag attributes taking into account the effect of monthly, seasonal, and annual history were considered. The performances of the forecasting models were assessed using various forecasting skill indicators. Moreover, an uncertainty analysis of the developed forecasting models was performed to evaluate the ability of the hybrid ANFIS models. The bound width of 95% confidence interval (d-factor) and the percentage of observed samples which was enveloped by 95% forecasted uncertainties (95PPU) were used for this purpose. The results indicated that all the hybrid ANFIS models performed better than the conventional ANFIS and for all input combinations. The obtained results showed that the models with best input combinations had the (95PPU and d-factor) values of (91.67 and 1.41), (91.03 and 1.41), (89.74 and 1.42), and (88.46 and 1.43) for ANFIS-PSO, ANFIS-GA, ANFIS-DE, and the conventional ANFIS, respectively. Based on the 95PPU and d-factor, it is concluded that all hybrid ANFIS models have an acceptable degree of uncertainty in forecasting monthly rainfall. The results of this study proved that the hybrid ANFIS with an evolutionary algorithm is a reliable modeling technique for forecasting monthly rainfall.

  • 19.
    Yaseen, Zaher Mundher
    et al.
    Sustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Ehteram, Mohammad
    Department of Water Engineering and Hydraulic Structures, Faculty of Civil Engineering, Semnan University.
    Sharafati, Ahmad
    Civil Engineering Department, Science and Research Branch, Islamic Azad University, Tehran.
    Shahid, Shamsuddin
    School of Civil Engineering, Universiti Teknologi Malaysia (UTM).
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    El-Shafie, Ahmed
    Civil Engineering Department, Faculty of Engineering, University of Malaya, Kuala Lumpur .
    The Integration of Nature-Inspired Algorithms with Least Square Support Vector Regression Models: Application to Modeling River Dissolved Oxygen Concentration2018In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 10, no 9, article id 1124Article in journal (Refereed)
    Abstract [en]

    The current study investigates an improved version of Least Square Support Vector

    Machines integrated with a Bat Algorithm (LSSVM-BA) for modeling the dissolved oxygen (DO)concentration in rivers. The LSSVM-BA model results are compared with those obtained using M5Tree and Multivariate Adaptive Regression Spline (MARS) models to show the efficacy of this novelintegrated model. The river water quality data at three monitoring stations located in the USA areconsidered for the simulation of DO concentration. Eight input combinations of four water quality parameters, namely, water temperature, discharge, pH, and specific conductance, are used to simulate the DO concentration. The results revealed the superiority of the LSSVM-BA model over the M5 Tree and MARS models in the prediction of river DO. The accuracy of the LSSVM-BA model compared with those of the M5 Tree and MARS models is found to increase by 20% and 42%, respectively, in terms of the root-mean-square error. All the predictive models are found to perform best when all the four water quality variables are used as input, which indicates that it is possible to supply more information to the predictive model by way of incorporation of all the water quality variables.

  • 20.
    Yousif, Ali A.
    et al.
    Water Resources Engineering Department, College of Engineering, University of Duhok, Duhok, Iraq.
    Sulaiman, Sadeq Oleiwi
    Dams and Water Resources Department, College of Engineering, University of Anbar, Ramadi, Iraq.
    Diop, Lamine
    UFR S2ATA, Sciences Agronomiques, de l’Aquaculture et des Technologies Alimentaires, Université Gaston Berger (UGB), Saint Louis, Sénégal.
    Etheram, Mohammad
    Department of Water Engineering and Hydraulic Structures, Faculty of Civil Engineering, Semnan University, Semnan, Iran.
    Shahid, Shamsuddin
    School of Civil Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, Johor Bahru, Malaysia.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Yaseen, Zaher Mundher
    ustainable Developments in Civil Engineering Research Group, Faculty of Civil Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
    Open Channel Sluice Gate Scouring Parameters Prediction: Different Scenarios of Dimensional and Non-Dimensional Input Parameters2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 2, article id 353Article in journal (Refereed)
    Abstract [en]

    The determination of scour characteristics in the downstream of sluice gate is highly importantfor designing and protection of hydraulic structure.  The applicability of modern data-intelligence technique known as extreme learning machine (ELM) to simulate scour characteristics has been examined in this study.  Three major characteristics of scour hole in the downstream of a sluice gate, namely the length of scour hole (Ls), the maximum scour depth (Ds), and the position of maximum scour depth (Lsm), are modeled using different properties of the flow and bed material. The obtained results using ELM were compared with multivariate adaptive regression spline (MARS). The dimensional analysis technique was used to reduce the number of input variable to a smaller number of dimensionless groups and both the dimensional and non-dimensional variables were used to model the scour characteristics. The prediction performances of the developed models were examined using several statistical metrics. The results revealed that ELM can predict scour properties with much higher accuracy compared to MARS. The errors in prediction can be reduced in the range of 79%–81% using ELM models compared to MARS models. Better performance of the models was observed when dimensional variables were used as input. The result indicates that the use of ELM with non-dimensional data can provide high accuracy in modeling complex hydrological problems.

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