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  • 1.
    Aalipour, Mojgan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Human Factors Approach for Maintenance Improvement2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The purpose of this research work is to explore and describe human factors affectingmaintenance execution. To achieve the purpose of this study, the influencing factors have been identified using a literature survey. They have been categorized into four main groups namely organizational, workplace, job and individual factors. The Analytical Hierarchy Process (AHP) method is employed on data questionnaires to rank the priority of the factors. The interrelationships between these factors have been recognized by theInterpretive Structural Modelling (ISM) model. In the present case studies, MICMAC1analysis technique is also implemented for identifying the driving, dependent, linkage and autonomous factors. The data was collected through a questionnaire survey involving the participation of 16 and 25 maintenance staff and 10 mining experts in Swedish and Iranian mines, respectively. Within the study, it has been identified that the temperature, work layout, tools design and tools availability are the most important factors in both mines related to these categories. However, the significant factors in the organizational and individual categories are different in the selected mines. The effect of workplace factors on the maintainability of mining equipment is discussed and thereafter a methodology for maintainability management in the design and operation phases is developed. In the thirdcase study HEART2 is applied to estimate the probability of human error occurring duringmaintenance execution in an Iranian cable company. This research supports maintenance management to gain knowledge of human factors that affect maintenance execution. Further, this understanding could be useful in the development of strategies to improve the execution of maintenance.Keywords: Human Factors, Maintenance Management, Human Reliability, HumanPerformance, AHP, ISM, MICMAC, HEART

  • 2.
    Aalipour, Mojgan
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Ayele, Yonas Zewdu
    Department of Engineering and Safety, UiT The Arctic University of Norway, Tromsø.
    Barabadi, Abbas
    Tromsø University, Department of Engineering and Safety, UiT The Arctic University of Norway, Tromsø.
    Human reliability assessment (HRA) in maintenance of production process: a case study2016In: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 7, no 2, p. 229-238Article in journal (Refereed)
    Abstract [en]

    Human reliability makes a considerable contribution to the maintenance performance, safety, and cost-efficiency of any production process. To improve human reliability, the causes of human errors should be identified and the probability of human errors should be quantified. Analysis of human error is very case-specific; the context of the field should be taken into account. The aim of this study is to identify the causes of human errors and improve human reliability in maintenance activities in the cable manufacturing industry. The central thrust of this paper is to employ the three most common HRA techniques—human error assessment and reduction technique, standardized plant analysis risk-human reliability, and Bayesian network—for estimating human error probabilities and then to check the consistency of the results obtained. The case study results demonstrated that the main causes of human error during maintenance activities are time pressure, lack of experience, and poor procedure. Moreover, the probabilities of human error, obtained by employing the three techniques, are similar and consistent

  • 3.
    Aalipour, Mojgan
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Barabadi, Abbas
    Tromsø University, University of Tromsø - The Arctic University of Norway.
    Maintainability management of production facilities in complex and challenging operating conditions2015In: 2015 IEEE International Conference on Industrial Engineering and Engineering Management (IEEM): Singapore, 6-9 Dec. 2015, Piscataway, NJ: IEEE Communications Society, 2015, p. 817-820, article id 7385761Conference paper (Refereed)
    Abstract [en]

    As equipment becomes more complex, repair process becomes more complicated, costly and time-consuming. Maintainability principles are developed to facilitate the repair process. Maintainability principles are applied in design phase and they are characteristic that affects time, accuracy, ease and safety requirements of the repair process. Considering Maintainability principles in the design phase are critical in challenging operational conditions such as Arctic offshore. To have an effective design for maintainability a systematic management approach is required during the design phase. This paper is developed a systematic guideline for maintainability management as an engineering discipline for challenges operational condition

  • 4.
    Aalipour, Mojgan
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Barabadi, Abbas
    Tromsø University, University of Tromsø - The Arctic University of Norway.
    Work place factors effect on maintainability in challenging operating conditions2015In: 2015 IEEE International Conference on Industrial Engineering and Engineering Management (IEEM): Singapore, 6-9 Dec. 2015, Piscataway, NJ: IEEE Communications Society, 2015, p. 767-771, article id 7385751Conference paper (Refereed)
    Abstract [en]

    Some industries such as mining industry create complex and challenging work place for maintenance crews. For example in an underground mine, for some machines, heavy maintenance tasks must be performed on site in a limited workspace in a harsh environment, including dust and improper illumination. Such operating conditions can increase the health, safety, and environment (HSE) risk, reduce the availability of the machines and increase the life cycle cost of equipment. A review of current mining equipment design and maintenance procedure confirms that considerable reduction in HSE risk, as well as substantial cost savings, can be achieved by considering human factors. This study discusses the effect of workplace factors on the maintainability of mining equipment. It presents the results from questionnaires on the effect of work place factors on maintainability performance given to maintenance staff at two mines, one in northern Sweden and the other in Iran.

  • 5.
    Aalipour, Mojgan
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Singh, Sarbjeet
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Identification of Factors affecting Human performance in Mining Maintenance tasks2014In: Proceedings of the 3rd international workshop and congress on eMaintenance: June 17-18 Luleå, Sweden : eMaintenance, Trends in technologies & methodologies, challenges, possibilites and applications / [ed] Uday Kumar; Ramin Karim; Aditya Parida; Philip Tretten, Luleå: Luleå tekniska universitet, 2014, p. 71-76Conference paper (Refereed)
    Abstract [en]

    This paper investigates the factors affecting humanperformance in maintenance task in mining sector. Theobjective is identify various factors and to classify them asdriving (strong driving power and weak dependence) anddependent factors (weak driving power and strongdependence). The factors were identified through literaturesurvey and are ranked using mean score of data questionnaire.The reliability of measures is pretested by applyingCronbach’s alpha coefficient to responses to a questionnairegiven to maintenance personnel. The interrelationshipsbetween human factors have been recognized by interpretivestructural modeling (ISM). Further, these factors have beenclassified using matrice d'impacts croises-multiplicationappliqué à un classement (MICMAC) analysing. This casestudy will figure out the factors affecting human performancefor deriving maintenance management insights to improveproductivity in the mining sector. Further, this understandingmay be helpful in framing the policies and strategies formining industry. Temperature, lighting, documentation,communication and fitness are driving factors. Moreover,Work layout, tools availability, complex tasks, time pressure,safety, boss decisions, training, fatigue and motivation havestrong driving power as well as high dependencies and itcomes under the category of linkage factors.

  • 6.
    Abbas, Nahla
    et al.
    School of Engineering and Technology, Central Queensland University, Melbourne .
    Wasimi, Saleh A.
    School of Engineering and Technology, Central Queensland University, Melbourne .
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Climate Change Impacts on Water Resources of Greater Zab River, Iraq: Climate Change Impacts on Water Resources of Greater Zab River, Iraq2016In: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 10, no 12, p. 1384-1402Article in journal (Refereed)
    Abstract [en]

    Greater Zab is the largest tributary of the Tigris River in Iraq where the catchment area is currently being plagued by water scarcity and pollution problems. Contemporary studies have revealed that blue and green waters of the basin have been manifesting increasing variability contributing to more severe droughts and floods apparently due to climate change. In order to gain greater appreciation of the impacts of climate change on water resources in the study area in near and distant future, SWAT (Soil and Water Assessment Tool) has been used. The model is first tested for its suitability in capturing the basin characteristics, and then, orecasts from six GCMs (general circulation models) with about half-a-century lead time to 2046~2064 and one-century lead time to 2080~2100 are incorporated to evaluate the impacts of climate change on water resources under three emission scenarios: A1B, A2 and

    B1. The results showed worsening water resources regime into the future.

  • 7.
    Abbas, Nahla
    et al.
    School of Engineering and Technology, Central Queensland University, Australia.
    Wasimi, Saleh A.
    School of Engineering and Technology, Central Queensland University, Australia.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Impacts of Climate Change on Water Resources in Diyala River Basin, Iraq2016In: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 10, no 9, p. 1059-1074Article in journal (Refereed)
    Abstract [en]

    Diyala River is the third largest tributary of the Tigris River running 445 km length and draining an area of 32,600 km2. The river is the major source of water supply for Diyala City for municipal, domestic, agriculture and other purposes. Diyala River Basin currently is suffering from water scarcity and contamination problems. Up-to-date studies have shown that blue and green waters of a basin have been demonstrating increasing variability contributing to more severe droughts and floods seemingly due to climate change. To obtain better understanding of the impacts of climate change on water resources in Diyala River Basin in near 2046~2064 and distant future 2080~2100, SWAT (soil and water assessment tool) was used. The model is first examined for its capability of capturing the basin characteristics, and then, projections from six GCMs (general circulation models) are incorporated  to assess the impacts of climate change on water resources under three emission scenarios: A2, A1B and B1. The results showed deteriorating water resources regime into the future.

  • 8.
    Abbas, Nahla
    et al.
    School of Engineering & Technology, Central Queensland University, Melbourne.
    Wasimi, Saleh A.
    School of Engineering & Technology, Central Queensland University, Melbourne.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Model-Based Assessment of Climate Change Impact on Isaac River Catchment, Queensland2016In: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, no 7, p. 460-470Article in journal (Refereed)
    Abstract [en]

    Isaac River catchment, which is located within Fitzroy basin in Central Queensland, Australia is mostly a semi-arid region, sparsely populated, but rife with economic activities such as mining, grazing, cropping and production forestry. Hydro-meteorological data over the past several decades reveal that the catchment is experiencing increasing variability in precipitation and streamflow contributing to more severe droughts and floods supposedly due to climate change. The exposure of the economic activities in the catchment to the vagaries of nature and the possible impacts of climate change on the stream flow regime are to be analyzed. For the purpose, SWAT model was adopted to capture the dynamics of the catchment. During calibration of the model 12parameters were found to be significant which yielded a R2 value of 0.73 for calibration and 0.66 for validation. In the next stage, six GCMs from CMIP3 namely, CGCM3.1/T47, CNRM-CM3, GFDLCM2.1, IPSLCM4, MIROC3.2 (medres) and MRI CGCM2.3.2 were selected for climate change projections in the Fitzroy basin under a very high emissions scenario (A2), a medium emissions scenario(A1B) and a low emissions scenario (B1) for two future periods (2046-2064) and (2080-2100). All GCMs showed consistent increases in temperature, and as expected, highest rate for A2 and lowest rate for B1. Precipitation predictions were mixed-reductions in A2 and increases in A1B and B1, and more variations in distant future compared to near future. When the projected temperaturesand precipitation were inputted into the SWAT model, and the model outputs were compared with the baseline period (1980-2010), the picture that emerged depicted worsening water resources variability.

  • 9.
    Abbas, Nahla
    et al.
    School of Engineering and Technology, Central Queensland University, Melbourne.
    Wasimi, Saleh A.
    School of Engineering and Technology, Central Queensland University, Melbourne.
    Bhattarai, Surya
    School of Medical and Applied Sciences, Centra l Queensland University, Melbourne .
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    The Impacts of Climate Change on Fitzroy River Basin, Queensland, Australia: The Impacts of Climate Change on Fitzroy River Basin, Queensland, Australia2017In: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 11, no 1, p. 38-47Article in journal (Refereed)
    Abstract [en]

    An analysis of historical data of Fitzroy River, which lies in the east coast of Australia, reveals that there is an increasing

    trend in extreme floods and droughts apparently attributable to increased variability of blue and green waters which could be due to

    climate change. In order to get a better understanding of the impacts of climate change on the water resources of the study area for near

    future as well as distant future, SWAT (soil and water assessment tool) model was applied. The model is first tested for its suitability in

    capturing the basin characteristics with available data, and then, forecasts from six GCMs (general circulation model) with about

    half-a-century lead time to 2046~2064 and about one-century lead time to 2080~2100 are incorporated to evaluate the impacts of

    climate change under three marker emission scenarios: A2, A1B and B1. The results showed worsening water resources regime into the

    future.

  • 10.
    Abbas, Nahla
    et al.
    School of Engineering & Technology, Central Queensland University, Melbourne.
    Wasimi, Saleh
    School of Engineering & Technology, Central Queensland University, Melbourne.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sultana, Nasrin
    RMIT University, Melbourne.
    Water resources problems of Iraq: Climate change adaptation and mitigation2018In: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 26, article id 6Article in journal (Refereed)
    Abstract [en]

    Iraq is suffering from water scarcity, and future predictions indicate that it could get worse due to changing climate. Arguably, climate change is one of the greatest challenges onfronting this region it could have significant adverse effects on water resources and hence the environment and economy, particularly in the agricultural sector. This study considers possible adaptation and mitigation measures that could be undertaken in response to climate change. To overcome this problem,adaptation measures at farm and government level were conferred. Farm-level adaptation comprises adopting crop modification, soil conservation, irrigation, changing crop calendar and planting of trees. The government role is to ensure success of these adaptation measures. The government should get involved and support the farmers financially and technologically.

  • 11.
    Abbas, Nahlah
    et al.
    The school of engineering & technology, Central Queensland University, Melbourne, Australia.
    Wasimi, Saleh A.
    The school of engineering & technology, Central Queensland University, Melbourne, Australia.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Impacts of Climate Change on Water Resources of Greater Zab and Lesser Zab Basins, Iraq, Using Soil and Water Assessment Tool Model2017In: International Journal of Environmental, Chemical, Ecological, Geological and Geophysical Engineering, ISSN 2010-376X, Vol. 11, no 10, p. 823-829Article in journal (Refereed)
    Abstract [en]

    The Greater Zab and Lesser Zab are the major tributaries of Tigris River contributing the largest flow volumes into the river. The impacts of climate change on water resources in these basins have not been well addressed. To gain a better understanding of the effects of climate change on water resources of the study area in near future (2049-2069) as well as in distant future (2080-2099), Soil and Water Assessment Tool (SWAT) was applied. The model was first calibrated for the period from 1979 to 2004 to test its suitability in describing the hydrological processes in the basins. The SWAT model showed a good performance in simulating streamflow. The calibrated model was then used to evaluate the impacts of climate change on water resources. Six general circulation models (GCMs) from phase five of the Coupled Model Intercomparison Project (CMIP5) under three Representative Concentration Pathways (RCPs) RCP 2.6, RCP 4.5, and RCP 8.5 for periods of 2049-2069 and 2080-2099 were used to project the climate change impacts on these basins. The results demonstrated a significant decline in water resources availability in the future.

  • 12.
    Abbas, Nahlah
    et al.
    School of Engineering & Technology, Central Queensland University, Melbourne, VIC 3000, Australia.
    Wasimi, Saleh A.
    School of Engineering & Technology, Central Queensland University, Melbourne, VIC 3000, Australia.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Baby, Sultana Nasrin
    Department of Geospatial Sciences, RMIT University, Melbourne, VIC 3000, Australia.
    Recent Trends and Long-Range Forecasts of Water Resources of Northeast Iraq and Climate Change Adaptation Measures2018In: Water, ISSN 2073-4441, Vol. 10, no 11, p. 1-19, article id 1562Article in journal (Refereed)
    Abstract [en]

    Iraq has been experiencing water resources scarcity, and is vulnerable to climate change.

    Analysis of historical data revealed that the region is experiencing climate change to a degree higher than generally reported elsewhere. The relationship between climate change and its effect on water resources of a region has been sparsely addressed in published literature. To fill that gap this research work first investigates if there has been a significant change in climate in the region, which has been found to be true. In the next stage, the research projects future climatic scenarios of the region based on six oft-used General CirculationModel (GCM) ensembles, namely CCSM4, CSIRO-Mk3.6.0, GFDL-ESM2M, MEROC5, HadGEM2-ES, and IPSL-CM5A-LR. The relationship between climate change and its impact on water resources is explored through the application of the popular, widely used SWAT model. The model depicts the availability of water resources, classified separately as blue and green waters, for near and distant futures for the region. Some of the findings are foreboding and warrants urgent attention of planners and decision makers. According to model outputs, the region may experience precipitation reduction of about 12.6% and 21% in near (2049–2069) and distant (2080–2099) futures, respectively under RCP8.5. Those figures under RCP4.5 are 15% and 23.4%, respectively and under RCP2.6 are 12.2% and 18.4%, respectively. As a consequence, the blue water may experience decreases of about 22.6% and 40% under RCP8.5, 25.8% and 46% under RCP4.5, and 34.4% and 31% under RCP2.6 during the periods 2049–2069 and 2080–2099, respectively. Green water, by contrast, may reduce by about 10.6% and 19.6% under RCP8.5, by about 14.8% and 19.4% under RCP4.5, and by about 15.8% and 14.2% under RCP2.6 during the periods 2049–2069 and 2080–2099, respectively. The research further investigates how the population are adapting to already changed climates and how they are

    expected to cope in the future when the shift in climate is expected to be much greater.

  • 13.
    Abbas, Nahlah
    et al.
    School of Engineering & Technology, Central Queensland University, Melbourne, Australia.
    Wasimia, Saleh A.
    School of Engineering & Technology, Central Queensland University, Melbourne, Australia.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Assessment of Climate Change Impact on Water Resources of Lesser Zab, Kurdistan, Iraq Using SWAT Model2016In: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, p. 697-715Article in journal (Refereed)
    Abstract [en]

    Kurdistan in northern Iraq, a semi-arid region, predominantly a pastureland, is nourished by Lesser Zab, which is the second major tributary of Tigris River. The discharge in the tributary, in recent times, has been experiencing increasing variability contributing to more severe droughts and floods supposedly due to climate change. For a proper appreciation, SWAT model has been used to assess the impact of climate change on its hydrological components for a half-centennial lead time to 2046-2064 and a centennial lead time to 2080-2100. The suitability of the model was first evaluated, and then, outputs from six GCMs were incorporated to evaluate the impacts of climate change on water resources under three emission scenarios: A1B, A2 and B1. The results showed worsening water resources regime.

  • 14.
    Abbas, Nahlah
    et al.
    School of Engineering & Techno logy, Central Queensland Univ ersity, Melbourne, Australia .
    Wasimia, Saleh A.
    School of Engineering & Techno logy, Central Queensland Univ ersity, Melbourne, Australia .
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Assessment of Climate Change Impacts on Water Resources of Al-Adhaim, Iraq Using SWAT Model2016In: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, p. 716-732Article in journal (Refereed)
    Abstract [en]

    SWAT model (Sediment and Water Assessment Tool) was used to evaluate the impacts of climate change on water resources in Al-Adhaim Basin which is located in north east of Iraq. Al-Adhaim River is the main source of fresh water to Kirkuk City, one of the largest cities of Iraq. Recent studies have shown that blue and green waters of the basin have been manifesting increasing variability contributing to more severe droughts and floods apparently due to climate change. In order to gain greater appreciation of the impacts of climate change on water resources in the study area in near and distant future, SWAT (Soil and Water Assessment Tool) has been used. The model is first tested for its suitability in capturing the basin characteristics, and then, forecasts from six GCMs with about half-a-century lead time to 2046-2064 and one-century lead time to 2080-2100 are incorporated to evaluate the impacts of climate change on water resources under three emission scenarios: A2, A1B and B1. The results showed worsening water resources regime into the future.

  • 15.
    Abbas, Nahlah
    et al.
    School of Engineering & Technology Central Queensland University, Melbourne, Australia.
    Wasimia, Saleh A.
    School of Engineering & Technology Central Queensland University, Melbourne, Australia.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Assessment of climate change impacts on water resources of Khabour in Kurdistan , Iraq using SWAT model2016In: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 24, p. 1-21, article id 10Article in journal (Refereed)
    Abstract [en]

    The Khabour River is one of five tributaries of Tigris River and the first river flows into Tigris River contributing to Tigris Flow by about 2 BCM at Zakho Station. The area of this catchment is 6,143 km2, of which 57% are located in Turkey and 43% in Iraq with a total length of 181 km. Khabour River is the main source of fresh water to Duhok City, one of the major cities of Kurdistan Region. Hydrometeorological data over the past several decades reveal that the catchment is experiencing increasing variability in precipitation and stream flow contributing to more severe droughts and floods presumably due to climate change. SWAT model was applied to capture the dynamics of the basin. The model was calibrated at Zakho station. The performance of the model was rather satisfactory; R2 and ENC were 0.5 and 0.51, respectively in calibration period. In validation process R2 and ENC were nearly consistent. In the next stage, six GCMs from CMIP3 namely, CGCM3.1/T47, CNRM-CM3, GFDL-CM2.1, IPSLCM4, MIROC3.2 (medres) and MRI CGCM2.3.2 were selected for climate change projections in the basin under a very high emissions scenario (A2), a medium emissions scenario (A1B) and a low emissions scenario (B1) for two future periods (2046-2064) and (2080-2100). All GCMs showed consistent increases in temperature and decreases in precipitation, and as expected, highest rate for A2 and lowest rate for B1. The projected temperatures and precipitation were input to the SWAT model to project water resources, and the model outputs were compared with the baseline period (1980-2010), the picture that emerged depicted deteriorating water resources variability.

  • 16.
    Abbasi, Hamon
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Velayat park: En plats för gränsöverskridande möten mellan människor med olika socioekonomisk status2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Tehran, the capital of Iran has undergone major urbanization in the last century, which has caused uncontrollable urban growth. Poor regulation and control of this growth has given rise to environmental problems including high air and water pollution. In turn, this has led to urban growth towards the mountains in the north, where the environment is better. However, this pressure to develop in the north has increased segregation of the city and created a clear social division of class between the northern and southern parts of the City.

    In light of this, and in the context of Tehran as an extremely dense city with limited green space, the City sees a possibility in transforming an unused military airport in the southern districts of the city into a new urban park.

    This master thesis explores how to reclaim the 270Ha former airfield and develop it as an urban park with strengthened links to surrounding neighbourhoods.

    The work aims to gain an understanding of how large vacant areas can become successful public areas and green places in the community. The work is based on urban theory and site analysis and brings forward design proposals for the park.

    Analysis work is divided into an investigative and exploratory stage. The investigative part includes literature studies, data collection and mapping of the city’s urban morphological development, taking into account physical and socio-economic processes. The exploratory part consisted of inventories, site studies and interviews in Tehran, as well as integration analysis with space syntax to explore accessibility and connections in the new park.

    Throughout the study shows how and why the city has evolved and highlights a connection between living in the southern districts, which are low-income areas, with also having poor access to public and recreation areas.

    This analysis forms the foundations for the design proposal, visualizations and programs presented about how the area can be designed as a new urban city park.

    In conclusion, the study highlights that in order to be able to develop new places or renew existing area’s, consideration must be given to urban morphological development. This includes the socio-economic and socio-ecological process. It further concludes, that a ecological viewpoint together with a understanding of the physical environment, the urban landscape identity and the need of people in the context needs to be brought together to plan and create parks and urban spaces

  • 17.
    Abdel-Khalek, N.A.
    et al.
    Central Metallurgical Research and Development Institute (CMRDI), Helwan, Cairo.
    Yassin, K.E.
    Central Metallurgical Research and Development Institute (CMRDI), Helwan, Cairo.
    Kota, Hanumantha Rao
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Kandel, A-H
    Chemistry Department, Faculty of Science, Helwan University.
    Effect of starch type on selectivity of cationic flotation of iron ore2012In: Transactions of the Institution of Mining and Metallurgy Section C - Mineral Processing and Extractive Metallurgy, ISSN 0371-9553, E-ISSN 1743-2855, Vol. 121, no 2, p. 98-102Article in journal (Refereed)
    Abstract [en]

    Cationic flotation is one of the most widely accepted technologies for upgrading siliceous iron ore using polysaccharides (mainly starches) as depressing agents for iron bearing minerals while floating silica with amines. In this paper, a group of starches are investigated as depressants for haematite. These starches are wheat, corn, rice, potato and dextrin. The role of starch type on the selectivity of the separation process has been studied through zeta potential, adsorption measurements as well as flotation tests. The effects of type of starch and pH of the medium have been studied. The results indicate that the selectivity of the separation process is strongly affected by the type of starch used, where better results are obtained with corn starch or wheat starch in comparison to the other types. Fourier transform infrared spectroscopy measurements indicated that the interaction between starches and haematite surface is intermolecular interaction

  • 18.
    Abdelnasser, Amr
    et al.
    Geological Engineering Department, Faculty of Mines, Istanbul Technical University; Geology Department, Faculty of Science, Benha University, Benha .
    Kumral, Mustafa
    Geological Engineering Department, Faculty of Mines, Istanbul Technical University.
    Zoheir, Basem
    Geology Department, Faculty of Science, Benha University.
    Karaman, Muhittin
    Geological Engineering Department, Faculty of Mines, Istanbul Technical University.
    Weihed, Pär
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    REE geochemical characteristics and satellite-based mapping of hydrothermal alteration in Atud gold deposit, Egypt2018In: Journal of African Earth Sciences, ISSN 0899-5362, Vol. 145, p. 317-330Article in journal (Refereed)
    Abstract [en]

    New geochemical data of the hydrothermal alteration zones associated with gold-bearing quartz veins at Atud mine are used for better understanding the ore evolution and exploration vectoring. ASTER and Landsat 8 OLI data are used to elucidate the distribution of gold-associated alteration zones. Three alteration zones are defined; zone 1 (sericite-kaolinite-quartz-pyrite), zone 2 (quartz-sericite-albite-pyrite), and zone 3 (chlorite-carbonate-epidote ± pyrite). Sericite and hydrothermal quartz are confined to the mineralized quartz veins. Fe-OH and OH-bearing minerals are observed along NW- and NE-trending shear zones in the Main Atud mine. The association of gold-bearing quartz veins and sericite alteration is constrained by processing ASTER- and OLI-imagery data. The geochemical data of the ore-enveloping hydrothermally altered rocks are used to assess the behavior of the REEs during the mineralization process. Mild enrichment in LREE and significant enrichment in the HREE are associated with sericite in zones (1) and (2) alterations. Carbonate alteration (zone 3) is enriched in LREE and in immobile HREE. Moreover, LREE and Eu anomalies have negative correlated with the Alteration Index (A.I.) and K2O index (K.I.) in zones 1 and 2, suggesting high mobility of LREE in K-rich hydrothermal fluids. On the other hand, HREE anomalies with increasing MgO index (M.I.) in alteration zone 3 may imply low solubility of these elements in alkaline solutions. Au anomalies linked to sericite/silica alteration is a rather meaningful vector for further exploration in the area.

  • 19.
    Abdullah, Twana
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Groundwater Vulnerability Using DRASTIC model Applied to Halabja Saidsadiq Basin, IRAQ2017Licentiate thesis, comprehensive summary (Other academic)
  • 20.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Salahalddin
    University of Sulaimani.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Groundwater assessment of Halabja Saidsadiq Basin, Kurdistan region, NE of Iraq using vulnerability mapping2016In: Arabian Journal of Geosciences, ISSN 1866-7511, E-ISSN 1866-7538, Vol. 9, no 3, article id 223Article in journal (Refereed)
    Abstract [en]

    Halabja Saidsadiq Basin is located in the northeastern part of Iraq covering an area of about 1278 km2 with a population of about 190,727. Groundwater is the principal source of water in this area. Agricultural practices within the basin are widespread and located close to groundwater wells. This poses imminent threat to these resources. DRASTIC model integrated with GIS tool has been used to evaluate the groundwater vulnerability of this area. In addition, theDRASTIC model was modified using nitrate concentrations and sensitivity analysis to modify the recommended weighting value to get accurate results. The modified rates were calculated using the relations between each parameterand the nitrate concentration in the groundwater based on the Wilcoxon rank-sum non-parametric statistical test. While, to calibrate all types of modifications, the Pearson’s correlation coefficient was applied. The standard vulnerability map of the studied basin classified the basin into four zones ofvulnerability index including very low (34 %), low(13 %), moderate (48 %), and high (5 %) vulnerability index, while the combined modification classified the area into five classes: very low (7 %), low (35 %), moderate (19 %), high (35 %),and very high (4 %). The results demonstrate that both modified DRASTIC rate and weight were dramatically superior to the standard model; therefore, the most appropriate method to apply is the combination of modified rate-weight.

  • 21.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Salahalddin
    University of Sulaimani, Kurdistan Region.
    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.
    Classification of groundwater based on irrigation water quality index and GIS in Halabja Saidsadiq basin, NE Iraq2016In: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 24, article id 5Article in journal (Refereed)
    Abstract [en]

    Assessment of groundwater for irrigation purpose is proposed using the Irrigation Water Quality Index (IWQI) within the GIS environment. The model was applied to several aquifers in the study basin. Water samples were collected from thirty-nine sites from both water wells and springs from the dry season (September 2014) and the wet season (May 2015). Samples were tested chemically and physically for several variables: EC, Ca+2, Mg+2, Cl-, Na+ and HCO3- and SAR. The accuracy and precision methods were applied to find out the uncertainty of the chemical analysis results and its validity of application for the geochemical interpretations. Based on the spatial distribution of IWQI, the groundwater quality of HSB classified into several classes of both dry and wet seasons in terms of its restrictions on irrigation purposes. The classes include, Severe Restriction (SR), High Restriction (HR) and Moderate Restriction (MR). The coverage areas of all three classes are 1.4%, 52.4% and 46.2% for the dry season and 0.7%, 83.3% and16% for wet seasons respectively. The considerable variations in all these classes have been noted from dry to wet seasons, this might be related to increasing the aquifer recharges from precipitation and decreasing the aquifer discharges by the consumers in the wet season. Then the model was validated based on the relation between the aquifer recharge and spatial distribution of IWQI, the result of this validation confirmed the outcome of this study.

  • 22.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Salahalddin
    University of Sulaimani.
    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.
    Groundwater Vulnerability Mapping Using Lineament Density on Standard DRASTIC Model: Case Study in Halabja Saidsadiq Basin, Kurdistan Region, Iraq2015In: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 7, no 10, p. 644-667Article in journal (Refereed)
    Abstract [en]

    Groundwater is the most important source of water in the Halabja-Saidsadiq Basin. In this study, to generate a map of groundwater pollution vulnerability of the basin, the standard DRASTIC method has been applied. Due to the close relation between lineament density and groundwater flow and yield, the lineament density map was applied to the standard DRASTIC model in order to ensure accuracy towards the consideration of the effects of potential vulnerability to contamination. A lineament map is extracted from Enhanced Thematic Mapper plus (ETM+) satellite imagery using different techniques in remote sensing and GIS. The lineament density map illustrates that only six classes of lineament density can be identified ranged from (0 - 2.4). The lineament density map was rated and weighted and then converted to lineament index map. This index map is an additional parameter which was added to the standard DRASTIC model so as to map the modified DRASTIC vulnerability in HSB. The standard vulnerability map, classified the basin into four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). While the modified model classified the area into four categories as well: very low (28.75%), low (14.31%), moderate (46.91%) and high (10.04%). The results demonstrate that there is no significant variation in the rate of vulnerability. Therefore, the nitrate concentration between two different seasons (dry and wet) was analyzed from (30) water wells, considerable variations in nitrate concentration from dry to wet seasons had been noted. Consequently, it confirmed that the HSB are capable to receive the contaminant because of suitability in terms of geological and hydrogeological conditions. Based on this verification, it could be claimed that the effect of lineament density is weak on the vulnerability system in HSB, because of its low density value.

  • 23.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Salahalddin
    University of Sulaimani, Sulaymaniyah.
    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.
    Groundwater Vulnerability Using DRASTIC and COP Models: Case Study of Halabja Saidsadiq Basin, Iraq2016In: Engineering, ISSN 1947-3931, Vol. 8, no 11, p. 741-760Article in journal (Refereed)
    Abstract [en]

    To avoid groundwater from contamination, the groundwater vulnerability tool can be examined. In this study, two methods were applied, namely: DRASTIC (Groundwater depth, Net recharge, Aquifer media, Soil map, Topography, Impact of vadose zone and Hydraulic Conductivity) and COP (Concentration of flow, Overlying layer and Precipitation) to model groundwater vulnerability to pollution. The result illustrated that four vulnerability classes were recognized based on both models including very low, low, moderate and high vulnerability classes. The coverage areas of each class are (34%, 13%, 48% and 5%) by DRASTIC model and (1%, 37%, 2% and 60%) by COP model, respectively. The notable dissimilarity between these two models was recognized. For this reason, nitrate elements were selected as a pollution indicator to validate the result. The concentrations of nitrate were recorded in two following seasons in (30) watering wells; as a result, the substantial variation was noted. This indicates that contaminants can be easily reached the groundwater due to its suitability in geological and hydrogeological conditions in terms of contaminant transportation. Based on this confirmation, the standard DRASTIC method becomes more sensible than COP method.

  • 24.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Department of Geology, University of Sulaimani.
    Ali, Salahalddin
    Department of Geology, University of Sulaiman.
    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.
    Possibility of Groundwater Pollution in Halabja Saidsadiq Hydrogeological Basin, Iraq Using Modified DRASTIC Model Based on AHP andTritium Isotopes2018In: Geosciences, ISSN 2076-3263, Vol. 8, no 7, article id 236Article in journal (Refereed)
    Abstract [en]

    An anthropogenic activity is one of the most severe environmental causes for groundwatercontamination in the urban area. Groundwater thought to be one of the principal sources of water supply in Halabja Saidsadiq Basin, and therefore its vulnerability evaluation to define areas that are more vulnerable to pollution is incredibly vital.  The objectives of this paper are to reveal weight modified of DRASTIC model based on the Analytical Hierarchical Process to estimate the proportional likelihood of groundwater resources pollution. Tritium isotopes analysis was chosen and applied as a pollution marker to confirm the result of this adjustment. Based on this modification, vulnerability classes that were achieved for the studied basin were alienated into five classes, including very low, low, medium, high, and very high, with vulnerability index value of (<100, >100–125, >125–150,>150–200, and >200), respectively.

  • 25.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Salahalddin
    University of Sulaimani, Kurdistan Region, NE 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.
    Vulnerability of groundwater to pollution using three different models inHalabja Saidsadiq basin, Iraq2017In: Proceedings of the 10th World Congress of European Water Resources Association ‘Panta Rhei’, 5-9 July 2017, Athens, Greece / [ed] George Tsakisis, Vassilakos A. Tsihrintzis, Harris Vangelis, Dimitris Tigkas, Athens: European Water Resources AssociationSSOCIATION , 2017, p. 1827-1834Conference paper (Refereed)
    Abstract [en]

    Halabja Saidsadiq Basin (HSB) is one of a major basin of Iraq in terms of groundwater reservoirs. Intensive agricultural practices and economic revolution are widespread and located close to groundwater wells, which pose imminent threats to these resources. Therefore, the most effective and realistic solution is to prevent the contamination of groundwater through. The present study targets the computation of the vulnerability of groundwater reservoirs of the study area. Three methods have been examined, namely DRASTIC, VLDA and COP to model a map of groundwater vulnerability for contamination. The standard DRASTIC vulnerability maps classified the basin of four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). The VLDA model also classified the area into four categories as well: low (2%), moderate (44%), high (53%) and very high (1%).Four vulnerability classes were recognized based on COP model including very low, low, moderate and high vulnerability classes with coverage areas of (1%, 37%, 2% and 60%) respectively. After constructing every vulnerability map, it required to be confirmed in order to estimate the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. Considerable variations in nitrate concentration on dry to wet seasons had been renowned. Consequently, it points toward that groundwater in the HSB are capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree

    and distribution of vulnerability classes acquired using VLDA model is more sensible.

  • 26.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Ali, Salahalddin
    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.
    Vulnerability of groundwater to pollution using VLDA model in Halabja Saidsadiq Basin, Iraq.2016In: IWA Specialist Groundwater Conference: Conference Proceedings & Book of Abstracts, 09-11 June 2016, Belgrade Serbia / [ed] Milan A. Dimkic, Belgrade: Jaroslav Cerni Institute for the Development of Water Resources , 2016, p. 72-75Conference paper (Refereed)
    Abstract [en]

    Groundwater considered being the most vital source of water in several regions in the world. Specifically in the Halabja-Saidsadiq Basin, groundwater plays an important role as one of the essential source of water supplies. Therefore, it needs to be taken care of. In this study, VLDA method applied to model a map of groundwater vulnerability to contamination. The VLDA models classified the area into four categories with different coverage areas: low (2%), moderate (44%), high (53%) and very high (1%). After constructing every vulnerability map, it required to be confirmed in order to estimate the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. The nitrate concentration on two different seasons (dry and wet) was analyzed from (30) watering wells, considerable variations in nitrate concentration from dry to wet seasons had been noted. Consequently, it points toward that groundwater in the HSB are capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree and distribution of vulnerability classes acquired using VLDA model is more sensible.

  • 27.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Department of Geology, University of Sulaimani.
    Ali, Salahalddin S.
    University of Sulaimani, Kurdistan Region .
    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.
    Assessing the Vulnerability of Groundwater to Pollution Using DRASTIC and VLDA Modelsin Halabja Saidsadiq Basin, NE, Iraq2016In: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 10, no 10, p. 1144-1159Article in journal (Refereed)
    Abstract [en]

    Groundwater plays important roles as one of the essential source of water supplies of the studied area. Consequently, it needs to be prevented from contamination. In this study, two methods have been examined, namely DRASTIC (depth to groundwater, net recharge, aquifer media, soil map, topography, impact of vadose zone and hydraulic conductivity) and VLDA (vadose zone lithology, land use patterns, depth to groundwater and aquifer media) to model a map of groundwater vulnerability for contamination of the basin. The standard DRASTIC vulnerability maps classified the basin of four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). While the VLDA model classified the area into four categories as well: low (2%), moderate (44%), high(53%) and very high (1%). The results demonstrate that there is a significant dissimilarity in the rate of vulnerability. Validation of the constructed maps is required to confirm the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. The nitrate concentration of two different seasons (dry and wet) was analyzed from (30) watering wells, considerable variations in nitrate concentration from dry to wet seasons had been noted. Consequently, it points toward that groundwater in the HSB (Halabja Saidsadiq Basin) is capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree and distribution of vulnerability level acquired using VLDA model is more sensible than that attained from the standard DRASTIC method .In addition, the DRASTIC models need to be modified based on the land use pattern, which clarifies the role of human activity on the vulnerability system.

  • 28.
    Abdullah, Twana O.
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Department of Geology, University of Sulaimani, Kurdistan Region, NE..
    Ali, Salahalddin S.
    University of Sulaimani, Kurdistan Region, NE 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.
    Vulnerability of groundwater to pollution using three different models in Halabja Saidsadiq basin, Iraq2017In: European Water, ISSN 1105-7580, Vol. 57, p. 353-359Article in journal (Refereed)
    Abstract [en]

    Halabja Saidsadiq Basin (HSB) is one of a major basin of Iraq in terms of groundwater reservoirs. Intensive agricultural practices and economic revolution are widespread and located close to groundwater wells, which pose imminent threats to these resources. Therefore, the most effective and realistic solution is to prevent the contamination of groundwater through. The present study targets the computation of the vulnerability of groundwater reservoirs of the study area. Three methods have been examined, namely DRASTIC, VLDA and COP to model a map of groundwater vulnerability for contamination. The standard DRASTIC vulnerability maps classified the basin of four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). The VLDA model also classified the area into four categories as well: low (2%), moderate (44%), high (53%) and very high (1%). Four vulnerability classes were recognized based on COP model including very low, low, moderate and high vulnerability classes with coverage areas of (1%, 37%, 2% and 60%) respectively. After constructing every vulnerability map, it required to be confirmed in order to estimate the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. Considerable variations in nitrate concentration on dry to wet seasons had been renowned. Consequently, it points toward that groundwater in the HSB are capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree and distribution of vulnerability classes acquired using VLDA model is more sensible.

  • 29.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Salahalddin, Ali
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Effect of Agricultural activities on Groundwater Vulnerability: Case Study of Halabja Saidsadiq Basin, Iraq2015In: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 23, no 10Article in journal (Refereed)
    Abstract [en]

    Groundwater is one of the main sources of water in Halabja-Saidsadiq Basin of northeast Iraq. It covers an area of 1278 square kilometers with population of about 190,727.In this study, the standard DRASTIC method has been applied to generate a map of groundwater pollution vulnerability of the basin. In addition, two different scenes of landsat Thematic Mapper (TM) were used with the aid of ERDAS IMAGINE software and the GIS technique to prepare digital image classification of the study basin. Supervised classification for level I of USGS was conducted with band combination RGB/742 to prepare The Land Use and Land Cover (LULC) map. The LULC map illustrates that only five classes of land use can be identified these are: barren, agricultural, vegetation, urban and wet land or water body. The LULC map converted to LULC index map. This index map has an additional parameter added to the standard DRASTIC model to map the modified DRASTIC vulnerability in the study basin. Nitrate concentration analysis was selected and added as a pollution indicator to validate this modification. In this study, the nitrate concentration between two different seasons (dry and wet) was analyzed from (30) water wells. The standard vulnerability map of the studied basin classified the basin into four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). While the combined modification classified the area into five classes: very low (1.17%), low (36.82%), moderate (17.57%), high (43.42%) and very high (1.02%). The results s that the modified DRASTIC model was dramatically superior to the standard model; therefore, the most appropriate method to apply is the combination of standard DRASTIC model with LULC index map. This conclusion is based on the results of nitrate content, as its concentration in the dry season is much lower than in the wet season.

  • 30.
    Abhale, Prakash Bansi
    et al.
    Global R and D, ArcelorMittal, Kolkatta.
    Yadav, Vishal Kumar
    Department of Metallurgy and Materials Engineering (MTM), Katholieke Universiteit, Leuven.
    Nurni, Viswanathan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Ballal, Bharath Nidambur
    Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology, Bombay.
    Efficient computation of gas flow in blast furnace in 3-D2012In: 6th Int. Congress on the Science and Technology of Ironmaking 2012, ICSTI 2012: Including Proceedings from the 42nd Ironmaking and Raw Materials Seminar, and the 13th Brazilian Symp. on Iron Ore, 2012, Vol. 1, p. 722-732Conference paper (Refereed)
    Abstract [en]

    Blast furnace continues to occupy prominent place among iron making technologies as it accounts for more than 90% of the hot metal produced in the world. In India, as a part of initiative from Ministry of Steel, efforts are being made to develop offline as well as online models with an aim to improve blast furnace performance. As a part of this effort, offline comprehensive models simulating the internal state of an operating blast furnace are being developed. Such comprehensive models involve systematic integration of various sub-models for gas flow, solid flow, reaction kinetics, enthalpy balance etc. Unlike in many other systems, these sub-processes are highly interlinked in blast furnace and hence call for large number of iteration among the sub-models which ultimately results in significant computation time. Our efforts in integration of these sub-models have indicated that the gas flow is one of the important bottle necks in achieving faster computation. This has led to a development of new and efficient computation scheme to simulate the gas flow in 2-D [1]. This new scheme provided efficient way of handling complex burden profile in a blast furnace. This paper presents the extension of this 2-D gas flow model to 3-D. Further, the 3-D model has been used to investigate the asymmetry in gas flow which can arise from blanking the tuyeres, asymmetric fusion or cohesive zone or formation scabs or scaffolds in the furnace behavior

  • 31. Abitew, Aymiro
    et al.
    Zeinali, Amin
    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.
    Hydraulic conductivity of tailings deposit used as dam construction material at Aitik mine in Sweden2013Conference paper (Refereed)
    Abstract [en]

    Distribution of vertical and horizontal hydraulic conductivity and their correlation to geotechnical parameters affecting the hydraulic conductivity of tailings deposit at Aitik mine have been determined. The investigation was carried out along three sections which cover approximately 3km2 of area and 4-5meters of thickness. 3-5 test pits have been excavated in each section and samples are collected from various levels. The horizontal hydraulic conductivity has been found to have a good relation with fraction of fine particles in the deposit and void ratio. However, similar to the results of Jantzer et al (2008) from the same mine, the vertical hydraulic conductivity did not correspond to void ratio. According to evaluation of existing empirical relations to estimate hydraulic conductivity from particle size analysis, Hazen formula (1911) gives 25 and 45 times the measured values of vertical and horizontal hydraulic conductivity respectively. On the other hand, Chapuis et al (2003) has not been succeeded for prediction of hydraulic conductivity of undisturbed samples from the investigated area. However, it gives comparatively good prediction of hydraulic conductivity for disturbed samples which are compacted to their field dry density.

  • 32. Abitew, Aymiro
    et al.
    Zeinali, Amin
    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.
    Hydraulic conductivity of tailings sand used for dam construction at Aitik mine in Sweden2012In: SWEMP 2012: International symposium on Environmental Issues and Waste Management in Energy and Mineral Production, 2012Conference paper (Refereed)
    Abstract [en]

    Distribution of vertical and horizontal hydraulic conductivity and their correlation to geotechnical parameters affecting the hydraulic conductivity of tailings deposit at Aitik mine have been determined. The investigation was carried out along three sections which cover approximately 3km2 of area and 4-5meters of thickness. 3-5 test pits have been excavated in each section and samples are collected from various levels. The horizontal hydraulic conductivity has been found to have a good relation with fraction of fine particles in the deposit and void ratio. However, similar to the results of Jantzer et al (2008) from the same mine, the vertical hydraulic conductivity did not correspond to void ratio. According to evaluation of existing empirical relations to estimate hydraulic conductivity from particle size analysis, Hazen formula (1911) gives 25 and 45 times the measured values of vertical and horizontal hydraulic conductivity respectively. On the other hand, Chapuis et al (2003) has not been succeeded for prediction of hydraulic conductivity of undisturbed samples from the investigated area. However, it gives comparatively good prediction of hydraulic conductivity for disturbed samples which are compacted to their field dry density.

  • 33.
    Abrahamsson, Filip
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Leaching of Pyrrhotite from Nickel Concentrate2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Non-oxidative acid leaching of pyrrhotite from Kevitsa’s Ni-concentrate and methods to recover by-products, have been investigated. Selective dissolution of pyrrhotite (Fe1-xS, 0<x<0.25) can enrich the content of the valuable metals, such as Ni and Co, in the final concentrate and will reduce the amount of Fe and S sent to the smelters. The pyrometallurgical smelting of leached concentrate will thus give less formation of smelter by-products in form of slag and SO2. The leaching was studied through an experimental design plan with parameter settings of  38.8% to 57.8% H2SO4 and temperatures from 60 to 100°C. The best results were obtained in experiments carried out at the lower experimental range. Leaching at 60°C with an initial acid concentration of 38.8% H2SO4 was found sufficient to selectively dissolve most of the pyrrhotite; leaving an enriched solid residue. A QEMSCAN analysis of the solid residue confirmed that most of the pyrrhotite had been dissolved and showed that pentlandite was still the main Ni-mineral. Chemical assays showed that more than 95% of the Ni, Co, and Cu remained in the final residue.

       The utilized leaching process generates by-products, in the form of large quantities of Fe2+ in solution and gaseous H2S. To recover Fe2+, crystallization of iron(ii) sulfate (FeSO4∙nH2O) from leach solution through cooling have been studied. The crystallized crystals were further dehydrated into the monohydrate (FeSO4∙H2O) through a strong sulfuric acid treatment (80%H2SO4). XRD analysis confirmed that FeSO4∙H2O was the main phase in the final crystals, and a chemical analysis showed a Fe content of about 30%, 1.5% Mg, 0.4% Ca, and 0.2% Ni.

       The possibility to leach the concentrate by circulating the acidic solution from the crystallization stage has been tested. The recirculation of the solution showed no negative effects, as the recoveries of elements and chemical assays of the final solid residue were found to be similar to the obtained assay when the concentrate was leached in a fresh solution.

  • 34.
    Abrahamsson, Lena
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Enander, Mats
    Olsson, Hans
    Luleå tekniska universitet.
    Ranhagen, Ulf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Fallstudierapport: Iggesunds bruk. Efterbehandlingen. Arbetsrapport1993Report (Other academic)
  • 35.
    Abrahamsson, Lena
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Enander, Mats
    Luleå tekniska universitet.
    Olsson, Hans
    Luleå tekniska universitet.
    Ranhagen, Ulf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Förstudie av massabalshanteringen vid Iggesunds kartongbruk: arbetsrapport1996Report (Other academic)
  • 36.
    Abrahamsson, Lena
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Kaplan, Alexander
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Product and Production Development.
    Johansson, Jan
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Rask, Kjell
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Fältholm, Ylva
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Bergquist, Bjarne
    Projekt: LUPO - globala länkar2010Other (Other (popular science, discussion, etc.))
  • 37.
    Abramov, A.A.
    et al.
    Moscow State Mining University, Moscow.
    Forssberg, Eric
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Chemistry and optimal conditions for copper minerals flotation: theory and practice2005In: Mineral Processing and Extractive Metallurgy Review, ISSN 0882-7508, E-ISSN 1547-7401, Vol. 26, no 2, p. 77-143Article in journal (Refereed)
    Abstract [en]

    Reliable information on the surface state of sulphide copper minerals and regularities of sulphidization and flotation of oxidized copper minerals, the composition of sorption layer on the mineral surface forming during its interaction with xanthate or dixanthogen, and the influence of collector forms sorption on the copper minerals floatability and on the optimal conditions for these minerals flotation and depression has been obtained at present. The determined physicochemical models in the form of quantitative equations have been derived for the optimal conditions of flotation and depression of copper minerals under changing pH value and of sodium sulphide, lime, cyanide, zinc–cyanide complexes additions. The equations derived were proven in the laboratory and industrial scale and can be used both in automatic control systems at plants and for improvement of technological processes of selective flotation of copper containing ores.

  • 38.
    Acosta, April Anne
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Behaviour of the Cold-formedTrapezoidal Sheet Overlap Jointin a Gerber Lapped Connection2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 39.
    Adamo, Nasrat
    et al.
    LTU team.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Mosul Dam Full Story: Safety Evaluations of Mosul Dam2016In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 6, no 3, p. 185-212Article in journal (Refereed)
    Abstract [en]

    Mosul Dam is the second biggest dam in the Middle East due to the capacity of its reservoir. Since the operation of this dam in 1986, it is suffering from seepage problems in the foundation of the dam due to the dissolution of gypsum and anhydrite layers under the foundation. This phenomenon has raised concern about the safety of the dam. Studies done during the recent years showed that grouting works can only be considered as a temporary solution at its best. It is clear now that while grouting must be continued search for long term solution must be sought if dam failure consequences are to be avoided. This must be done as soon as possible as the dam is showing more and more signs of weakness. It is further considered that the suggestions and recommendations forwarded by the team of Lulea University of Technology and the Panel of Experts in the Stockholm Workshop 24-25 May, 2016 give the most practical and suitable solutions for this problem.

  • 40.
    Adamo, Nasrat
    et al.
    LTU team.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Mosul Dam Full Story: What If The Dam Fails?2016In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 6, no 3, p. 245-269Article in journal (Refereed)
    Abstract [en]

    Dams are very important infrastructure to any country where they serve for different purposes. Unfortunately, they represent risks to life and property due to their potential to fail and cause catastrophic flooding. Recent studies indicate the possibility of Mosul Dam failure. For this reason different failure models were used to estimate the consequences of such failure. Almost all models applied gave similar results. It is assumed that in case the water level in Mosul Dam reservoir is at its maximum operational level the effected population will reach 6,248,000 (about one million will lose their life) and the inundated area will be 7202 square kilometer. This catastrophe requires prudent emergency evacuation planning to minimize loses.

  • 41.
    Adamo, Nasrat
    et al.
    LTU team.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Mosul Dam the Full Story: Engineering Problems2016In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 6, no 3, p. 213-244Article in journal (Refereed)
    Abstract [en]

    The idea of building of Mosul Dam project started in 1950 and it was referred to as Aski Mosul Dam. Since that time, number of companies worked on the site selection and design of the dam. All the above companies suggested that the dam should be Earth-fill type with compressed clay core but there were different views about the exact location of the dam, spillway and electricity generating station. Grouting was suggested to be performed under the dam, spillway and the electricity generating station. In addition, they suggested that detailed geological investigation should be performed before any construction activities. In 1978, the Swiss Consultants Consortium was asked to be the consultants for Mosul Dam project. The consultants suggested that the operational water level at the dam to be 330 m (a.s.l.) while the flood and normal water levels to be 338 and 335 m (a.s.l.), respectively. The work started on 25th January, 1981 and finished 24th July, 1986. The foundation of the dam is built on alternating beds of limestone and gysum. Seepages due to the dissolution of gypsum were noticed and after impounding in 1986, new seepage locations were recognized. Grouting operations continued and various studies were conducted to find suitable grout or technique to overcome this problem. The seepage due to the dissolution of gypsum and anhydrite beds raised a big concern about the safety of the dam and its possible failure. It is believed that grouting will not solve this problem permanently

  • 42.
    Adamo, Nasrat
    et al.
    LTU team.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Issa, Issa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sissakian, Varoujan
    Consultant Geologist, Erbil.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Mystery of Mosul Dam the Most Dangerous Dam in the World: Experts Proposals and Ideas on Mosul Dam2015In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 5, no 3, p. 79-93Article in journal (Refereed)
    Abstract [en]

    During and after the construction of Mosul Dam, in Iraq, all the studies expressed a clear concern on the fact that the region of the dam suffers from extensive presence of soluble rock formations that might undermine the safety of the dam with its large reservoir. Most of the studies dealt with foundation treatment and safety hazards due to the dissolution of gypsum and anhydrite. To overcome the problem, grouting operations were performed. The seepage of water continued and this highlighted the possibility of the dam failure. Different grouting techniques and methods were suggested but the results were the same. Finally, it was decided to limit the maximum operation water level to EL. 319 m (a.s.l.) instead of EL.330 m (a.s.l.). This recommendation has remained in force up to now with the loss of sizable storage of irrigation water and power potential

  • 43.
    Adamo, Nasrat
    et al.
    LTU team.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Issa, Issa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sissakian, Varoujan
    Consultant Geologist, Erbil.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Mystery of Mosul Dam the most Dangerous Dam in the World: Foundation Treatment during Construction2015In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 5, no 3, p. 59-69Article in journal (Refereed)
    Abstract [en]

    Mosul dam was constructed on the beds of Fatha Formation (Middle Miocene). The beds of the formation are about 250 m thick composed of Marls, chalky limestone; gypsum, anhydrite, and limestone form a layered sequence. They are highly karstified. As a consequence, plenty of grouting operations were carried out to fill all the cavities, fractures, joints and to stop the seepage under the foundation of the dam. The main grouting operations were Blanket grouting and deep grout curtain. It was necessary to perform an extensive maintenance program to control the seepage process within the grouted zone to stop dissolution of gypsum and protect the safety of the dam.

  • 44.
    Adamo, Nasrat
    et al.
    LTU team.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Issa, Issa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sissakian, Varoujan
    Consultant Geologist, Erbil.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Mystery of Mosul Dam the Most Dangerous Dam in the World: Maintenance Grouting2015In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 5, no 3, p. 71-77Article in journal (Refereed)
    Abstract [en]

    Dissolution of gypsum and anhydrite at the foundation of Mosul Dam continued after its construction since 1986 onwards. After impounding, acceptable residual permeability could not be reached and new areas of high grout takes appeared in some other locations. New grout mixes were tested and even methods of delivering and injecting large grout quantities were developed. Sandy mixes were developed by adding certain weight of sand to the cement mix. In addition, pouring gravel after completion of grouting in large takes' zones was performed. As a result of gravel addition, it was concluded that it was not effective and very difficult to pour. Massive grouting was used where bentonite was added to the mix. Piezometric observation was used for checking the conditions of the grout curtain and the detection of problematic areas where additional treatment was required. Massive grouting, however, did not stop the dissolution processes altogether and it seems that it is not likely to do so in the future. The continuation of this program year after year does not preclude some bad implications. More research work is required to improve massive grout durability by adding chemicals which may interact with gypsum beds and hinder dissolution. This can help to improve gypsum resistance and increase its stability. Mathematical models might also be used to understand the mechanism of cavities formation and collapsing.

  • 45.
    Adamo, Nasrat
    et al.
    LTU team.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Issa, Issa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sissakian, Varoujan
    Consultant Geologist, Erbil.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Mystery of Mosul Dam the most Dangerous Dam in the World: Problems Encountered During and after Impounding the Reservoir2015In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 5, no 3, p. 47-58Article in journal (Refereed)
    Abstract [en]

    Mosul dam was built on the River Tigris northern part of Iraq during the period 25th January, 1981 and finished on 24th July, 1986. The foundation of the dam lies on the Fatha Formation. This formation is composed of alternating beds of marls, limestone, gypsum and clay. The beds of this formation are highly karstified. After impounding, several sinkholes developed within the vicinity of the dam site. The surface expression of the sinkholes suggests that they are caused by underground collapse.The appearance of the downstream sinkholes is most likely related to fluctuations in the tail water level of the main dam during operation of the dam and the downstream regulating reservoir. In addition, water seepage also was noticed in various areas indicating the dissolution of gypsum and anhydrite from the foundation. During the period February-August, 1986 the dissolution intensity ranged from 42 to 80 t /day.

  • 46.
    Adamo, Nasrat
    et al.
    LTU team.
    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.
    Laue, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sissakian, Varoujan
    Erbil, Iraq.
    Mosul Dam: A Catastrophe yet to unfold2017In: Engineering, ISSN 1947-3931, Vol. 9, no 3, p. 263-278Article in journal (Refereed)
    Abstract [en]

    Mosul Dam is multipurpose earth fill dam 3.4km long, 113m in height and its storage capacity reaches 11.11 km3 of which 2.95 km3 dead storage. The dam is located on the River Tigris in the northern part of Iraq about 60km north west Mosul city. The dam was built on highly karstified alternating beds of gypsum, marl and limestone. The dam was operating in 1986 and since then, seepage problems started due to the solubility of the gypsum beds, presence of karstification and the effect of the local groundwater aquifer. To stop the seepage insensitive grouting program was put to ensure the stability of the dam. Despite the injection of large quantities of grouting material, it did not stop the seepage. The situation became worse in 2014 when ISIS occupied the dam area and grouting operations were halted. Recent evaluation of the conditions indicates that the dam is in its worst conditions.

    The failure models of the dam indicate that 6 million people will be affected, and 7202km2 of land will be inundated. It is believed that to stop this catastrophe, grouting operations should be continued intensively to elongate the span life of the dam. As a permanent solution, another dam should be built downstream Mosul Dam so that it can take the wave of Mosul Dam in case of its failure.

  • 47.
    Adamo, Nasrat
    et al.
    LTU team.
    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.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sissakian, Varoujan
    Department of Geology, University of Kurdistan, Hewler.
    Risk Management Concepts in Dam Safety Evaluation:Mosul Dam as a Case Study2017In: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 11, no 7, p. 635-652Article in journal (Refereed)
    Abstract [en]

    Gradual shift has been observed lately of dam safety procedures from the conventional technical based towards a widerscope of risk management procedure based on risk analysis. The new approach considers the likelihood level of occurrence of a multitude of hazards and the magnitude of the resulting possible consequences in case of failure using rational cause and effect arguments. Most dam owners are shifting towards the use of the new risk based procedures; and even governments themselves are moving towards formalizing the new trend. Legislations in the United States were promulgated [1] after serious dam failures and the adoption of stringent levels of scrutiny led such federal dam owners to pioneer in this field and in developing the concepts and methods required. The corner stone in risk analysis is the definition of the potential modes that may lead to failure and assessment of the likelihood levels of their occurrence and possible category of the consequences which, after thorough evaluation, will shape thedecision making. This type of analysis was applied to Mosul Dam as a case study and resulted in definite recommendations.

  • 48.
    Adamo, Nasrat
    et al.
    LTU team.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sissakian, Varoujan K.
    University of Kurdistan, Howler, KRG, Iraq and Private Consultant Geologist, Erbil, Iraq .
    Knutsson, Sven
    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.
    Climate Change: Consequences on Iraq’s Environment2018In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 8, no 3, p. 43-58Article in journal (Refereed)
    Abstract [en]

    Iraq as a country is now suffering from Climate Change Impacts in similar or even worse ways than many other countries of the world. The manifestations of these climate changes are being felt in global warming, changes to weather driving elements and sea level rise. Increasing temperatures, declining precipitation rates and changed distribution patterns together with increasing evaporation are causing water stress in Iraq. However, they trigger other changes in a sort of chain reaction; such as droughts, desertification and sand storms. Iraq is not even safe from the consequences of sea level rise where the southern part of the Tigris- Euphrates delta is threatened by inundation and Iraq’s ports and sea coast line are endangered by such projected rise. So far the agricultural sector in Iraq has been hit very badly by the reduced water availability for arable lands; whether rain fed lands as in the northern part, or irrigated lands using the declining discharges of the Tigris and Euphrates Rivers as in the southern and middle parts. These discharges have already been additionally strained by the unfair sharing practiced by Turkey from which most of the two rivers’ water resources originate. The present negative climate change trends seem to be continuing in the future as it is obvious from all projections and studies being performed so far. Loss of cultivable land to desertification, recurrent droughts and sand storms and declining agriculture are the pattern of change in Iraq’s already fragile environment; and this will result inevitably in much more distress for the population in the future and will lead to social unrest. These will add to the great pressures facing all future governments unless the government takes protective planning and solutions.

  • 49.
    Adamo, Nasrat
    et al.
    LTU team.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sissakian, Varoujan
    University of Kurdistan, Howler, KRG.
    Knutsson, Sven
    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.
    Climate Change: The Uncertain Future of Tigris River Tributaries’ Basins2018In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 8, no 3, p. 75-93Article in journal (Refereed)
    Abstract [en]

    Global warming is hitting all parts of the world for the last fifty years due to Global Climate Change and it is expected to continue in the future in an increasing trend unless the present mode of CO2 emission is limited or reversed. This is manifested in the rising temperature over land and the changes induced in the general weather circulation patterns over land and oceans. The Tigris River catchment as most of other parts in the world is suffering from increased temperatures and reduced precipitation contributing to reduced water resources elements all over it and reduction of the river stream flow itself. Studies using the soil and water assessment tool SWAT were performed on the five Tigris River tributaries basins in Iraq in order to assess these impacts. This paper summarizes the results of those studies, the characteristics of each of the five basins, and illustrates the application of SWAT as a tool for future predictions. Moreover, it explains in more details the work done on one of the basins as an example, summarizes the results of the five studies and then analyzes these results and discusses the expected future outcomes. The final conclusion which can be drawn is that severe shortage in all water resources elements will occur over the five basins and the Tigris River stream flow will suffer a considerable decline. This situation demands that policy makers in Iraq should take steps immediately to improve water and soil management practices to try and reduce as much as possible the expected damage that will hit all water using sectors.

  • 50.
    Adamo, Nasrat
    et al.
    LTU team.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sissakian, Varoujan
    University of Kurdistan, Erbil.
    Knutsson, Sven
    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.
    Is Mosul Dam the Most Dangerous Dam in the World?: Review of Previous Work and Possible Solutions2017In: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 9, no 10, p. 801-823, article id 79510Article in journal (Refereed)
    Abstract [en]

    Mosul Dam is an earth fill dam located on the Tigris River in North Western part of Iraq. It is 113 m in height, 3.4 km in length, 10 m wide in its crest and has a storage capacity of 11.11 billion cubic meters. It is, constructed on be- drocks which consist of gypsum beds alternated with marl and limestone, in cyclic nature. The thickness of the gypsum beds attains 18 m; they are in- tensely karstified even in foundation rocks. This has created number of prob- lems during construction, impounding and operation of the dam. Construc- tion work in Mosul Dam started on January 25th, 1981 and started operating on 24th July, 1986. After impounding in 1986, seepage locations were recog- nized. The cause of seepage is mainly due to: 1) The karsts prevailing in the dam site and in the reservoir area. 2) The existence of gypsum/anhydrite rock formations in the dam foundation alternating with soft marl layers and wea- thered and cavernous limestone beddings. 3) The presence of an extensive ground water aquifer called Wadi Malleh aquifer, which affects considerably the ground water regime in the right bank. The dissolution intensity of the gypsum/anhydrite ranged from 42 to 80 t/day which was followed by a noti- ceable increase in the permeability and leakages through the foundation. In- spection of the dam situation in 2014 and 2015 indicates that the dam is in a state of extreme unprecedentedly high relative risk. In this work, possible so- lutions to the problem are to be discussed. It is believed that grouting opera- tions will elongate the span life of the dam but do not solve the problem. Building another dam downstream Mosul Dam will be the best protective measures due to the possible failure of Mosul Dam, to secure the safety of thedownstream area and its’ population.

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