Change search
Refine search result
1234567 1 - 50 of 43708
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 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. Aaltonen, Sanna
    et al.
    Sunnari, Vappu
    Sexual harassment: conceptual and methodological reflections2001In: Youth on the threshold of 3rd millennium, Joensuu: Joensuun yliopisto , 2001, p. 31-44Chapter in book (Other academic)
  • 7.
    Aardal, Karen
    et al.
    Department of Mathematics, Linköping Institute of Technology.
    Ari, Aysen
    Luleå tekniska universitet.
    Decomposition principles applied to the dynamic production and work-force scheduling problem1987In: Engineering Costs and Production Economics, ISSN 0167-188X, E-ISSN 1878-4011, Vol. 12, no 1-4, p. 39-49Article in journal (Refereed)
    Abstract [en]

    One of the most important problems in the production and inventory planning field, is the scheduling of production and work force in a dynamic environment. Although this problem can be formulated as a linear program, it is often quite difficult to solve directly, due to its large scale. Instead, it might be fruitful to use a decomposition approach. Decomposition, in general, means decomposing a difficult problem into several easier, or a sequence of easier problems which are later coordinated to reconstruct the original problem.In this report we discuss several possibilities of applying the most common decomposition principles, namely Benders (primal) and Datnzig-Wolfe (dual), as well as a relatively new decomposition method, called cross decomposition, to the dynamic, multiproduct production and employment planning problem. A number of special cases are also presented.

  • 8.
    Aardal, Karen
    et al.
    CORE, Université Catholique de Louvain, Louvain-la-Neuve, Belgium.
    Ari, Aysen
    Luleå tekniska universitet.
    On the resemblance between the Kornai-Liptak and cross decomposition techniques for block-angular linear programs1990In: European Journal of Operational Research, ISSN 0377-2217, E-ISSN 1872-6860, Vol. 46, no 3, p. 393-398Article in journal (Refereed)
    Abstract [en]

    In this paper the resemblance is demonstrated between the master- and subproblems generated by the Kornai-Liptak algorithm and the subproblems obtained by using the cross decomposition method on linear optimization problems with block-angular structure. The significance of the similarity between these two algorithms becomes apparent considering the main disadvantage attributed to cross decomposition. In cross decomposition a master problem has to be solved from time to time since the subproblems alone do not always give a converging sequence of primal and dual solutions. But if the cross decomposition algorithm is modified in such a way that the successive primal and dual subproblem solutions are taken into consideration with equal weights, this results in the Kornai-Liptak algorithm for which convergence is guaranteed

  • 9.
    Aarrevaara, Timo
    et al.
    Helsingfors Universitet.
    Berg, Elisabeth
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Introduction2014In: Higher Education and Research in Academe: Who should pay?, Luleå: Luleå tekniska universitet, 2014, p. 11-17Chapter in book (Other academic)
  • 10.
    Aas, Gro Hanne
    Luleå tekniska universitet.
    Kvinneforskningspolitiske (pr)øvelser1999Licentiate thesis, comprehensive summary (Other academic)
    Abstract [no]

    Målsettingen for licentiatuppsatsen er å analysere nordisk kvinneforsknings formuleringer av forskningspolitiske felter, problemstillinger og utfordringer, og gjennom kontakt og diskusjon bidra til samarbeid, diskusjoner og offentlighet om forskingspolitikk i kvinneforskning. Arbeidet har tatt utgangspunkt i relativt nytt materiale fra Danmark, Norge og Sverige. I kap. 1 presenteres prosjektet, problemstillinger og materiale. Kapitlene 2-6 består av innledninger og artikler holdt eller skrevet i løpet av de to senaste åren. Diskusjoner om kjønn og akademia står i fokus i kap. 2 - "Universities have politics". I kap. 3, artikkelen "Gamle og nye drømmer", diskuteres et kvinneforskningspolitiske intervensjonsprosjekt som blev utført for en del år tilbake, og det antydes noen nye omdreiningspunkter for et slikt arbeid. Enkelte perspektiver utdypes i kap. 4, "Kvinneforskningens samfunnskontrakt", hvor termen "kvinneperspektiv" som forskningspolitisk term granskas krtitiskt. De to siste kapitlene tar utgangspunkt i den norske forskningsmeldingen som kom våren 1999. Ut fra tre lesestrategier forsøkes det leses muligheter for kvinneforskningspolitiske strategier. Det ses også på innholdet i regjeringens forskningspolitiske verdidebatt, og det diskuteres mulige intervensjoner i denne ut fra feministiske vitenskaps- og teknologistudier.

  • 11.
    Aasa, Björn
    et al.
    Department of Orthopaedics, Surgical and Perioperative Sciences, Umeå University, Norrlandsklinikens hälsocentral, Umeå.
    Berglund, Lars
    Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University.
    Michaelson, Peter
    Luleå University of Technology, Department of Health Sciences, Health and Rehab.
    Aasa, Ulrika
    Umeå University, Department of Community Medicine and Rehabilitation.
    Individualized Low-Load Motor Control Exercises and Education Versus a High-Load Lifting Exercise and Education to Improve Activity, Pain Intensity, and Physical Performance in Patients With Low Back Pain: A Randomized Controlled Trial2015In: Journal of Orthopaedic and Sports Physical Therapy, ISSN 0190-6011, E-ISSN 1938-1344, Vol. 45, no 2, p. 77-85Article in journal (Refereed)
    Abstract [en]

    Study DesignRandomized controlled trial. BackgroundLow back pain is a common disorder. Patients with low back pain frequently have aberrant and pain-provocative movement patterns that often are addressed with motor control exercises. ObjectiveTo compare the effects of low-load motor control (LMC) exercise and those of a high-load lifting (HLL) exercise. MethodsSeventy participants with recurrent low back pain, who were diagnosed with nociceptive mechanical pain as their dominating pain pattern, were randomized to either LMC or HLL exercise treatments. Participants were offered 12 treatment sessions over an 8-week period. All participants were also provided with education regarding pain mechanisms. MethodsParticipants were assessed prior to and following treatment. The primary outcome measures were activity (the Patient-Specific Functional Scale) and average pain intensity over the last 7 days (visual analog scale). The secondary outcome measure was a physical performance test battery that included 1 strength, 3 endurance, and 7 movement control tests for the lumbopelvic region. ResultsBoth interventions resulted in significant within-group improvements in pain intensity, strength, and endurance. The LMC group showed significantly greater improvement on the Patient-Specific Functional Scale (4.2 points) compared with the HLL group (2.5 points) (P<.001). There were no significant between-group differences in pain intensity (P = .505), strength, and 1 of the 3 endurance tests. However, the LMC group showed an increase (from 2.9 to 5.9) on the movement control test subscale, whereas the HLL group showed no change (from 3.9 to 3.1) (P<.001). ConclusionAn LMC intervention may result in superior outcomes in activity, movement control, and muscle endurance compared to an HLL intervention, but not in pain intensity, strength, or endurance. Registered at ClinicalTrials.gov (NCT01061632).

  • 12.
    Aasa, Björn
    et al.
    Norrlandsklinikens hälsocentral, Umeå.
    Hellqvist, Jonas
    Umeå University, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Berglund, Lars
    Umeå University, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Michaelson, Peter
    Luleå University of Technology, Department of Health Sciences, Health and Rehab. peter.michaelson@ltu.se .
    Aasa, Ulrika
    Umeå University, Department of Community Medicine and Rehabilitation, Physiotherapy.
    A characterisation of pain, disability, kinesiophobia and physical capacity in patients with predominantly peripherally mediated mechanical low back pain2011In: Physiotherapy, ISSN 0031-9406, E-ISSN 1873-1465, Vol. 97, no Suppl. 1Article in journal (Refereed)
    Abstract [en]

    Purpose: The specific objectives were to: 1) describe the level of pain intensity, disability, activity limitation, kinesiophobia and physical capacity in patients with predominantly peripherally mediated mechanical back pain, and 2) investigate whether differences between these patients in physical and psychosocial factors can be distinguished when the patients are further sub-grouped.Relevance: To improve assessment among patients with chronic low back pain (CLBP) it is important to investigate the prevalence of physical and psychosocial features in homogenous sub-groups.Participants: Seventy-one patients with CLBP, 20-60 years old, with peripherally mediated mechanical pain at the the moment for the study, were included and each patient was sub-classified into one of five sub-groups based on their pain behaviour and functional movement pattern (flexion n=20, flexion/lateral shift, n=11, active extension n=23 , passive extension n=8, and multidirectional pattern n=9).Methods: Data on pain intensity (Visual Analogue Scale), disability (the Roland and Morris Questionnaire), activity limitation (the Patient Specific Functional Scale), kinesiophobia (the Tampa Scale of Kinesiophobia) and physical capacity (lifting capacity and trunk extensor endurance) was collected.Analysis: Mean and standard deviation for parametric and median and interquartile range for non-parametric data were used for descriptive statistics. One-way ANOVA for normally distributed data and Kruskal-Wallis for non-normally distributed data were used for analyses of differences between the sub-groups. The subjects were also divided into two age-groups (20-40 and 41-60 years) and measures of physical capacity were compared to women and men at the ages of 34 and 50, respectively, in the general Swedish population using one sample T-test.Results: The patients reported low to moderate pain intensity (3.1/10±2.4), disability (RMDQ (7.27/24 ±4.2) and kinesiophobia (33.4/68 ±7) and these levels were lower than reported levels in other studies including more heterogenous groups of patients with CLBP. The patiens reported activity limitations (PSFS 13/30±23). Lifting capacity and trunk extensor endurance were significantly lower than in the general population in the youngest age-group. No significant differences in pain intensity, disability, kinesiophobia or physical capacity were found between the sub-groups.Conclusions: This research highlights that patients with predominantly peripherally mediated mechanical back pain may differ from other sub-groups of patients with CLBP (e.g., patients with central sensitization as dominating pain mechanism) regarding physical and psychosocial factors. The individual variation in pain intensity, disability, kinesiophbia and physical capacity among the patients indicates the importance to assess these factors in every patient. Due to the fact that there were few patients in the sub-groups, further research is necessary to explore whether there are differences, that we were not able to disingjish, between patients with different movement patterns.

  • 13.
    Aasa, Björn
    et al.
    Department of Orthopaedics, Surgical and Perioperative Sciences, Umeå University, Norrlandsklinikens hälsocentral, Umeå.
    Sandlund, Jonas
    Michaelson, Peter
    Luleå University of Technology, Department of Health Sciences, Health and Rehab.
    Aasa, Ulrika
    Umeå University, Department of Community Medicine and Rehabilitation.
    Low- versus high-load motor control exercise to reduce disability in patients with persistent peripherally mediated mechanical low back pain2012In: Rendez vous of hands and minds: 10th International Federation of Orthopaedic Manipulative Physical Therapists’ World conference, Quebec,  1-5 Oct 2012, 2012, no 2Conference paper (Refereed)
  • 14.
    Aasa, Ulrika
    et al.
    Umeå University, Department of Community Medicine and Rehabilitation.
    Aasa, Björn
    Department of Orthopaedics, Surgical and Perioperative Sciences, Umeå University, Norrlandsklinikens hälsocentral, Umeå.
    Michaelson, Peter
    Luleå University of Technology, Department of Health Sciences, Health and Rehab.
    Sandlund, Jonas
    Effects of low- and high-load motor control exercises on lumbar curvature during stance in patients with low back pain2012In: Rendez vous of hands and minds: 10th International Federation of Orthopaedic Manipulative Physical Therapists’ World conference, Quebec,  1-5 Oct 2012, 2012, no 2Conference paper (Refereed)
  • 15.
    Aava, Nils
    et al.
    Luleå tekniska universitet.
    Ericson, Ronald
    Luleå tekniska universitet.
    Esberg, Lars
    Luleå tekniska universitet.
    Belysning i bilverkstäder: förslag till belysningsplanering1979Report (Other academic)
  • 16.
    Abadei, S
    et al.
    Chalmers University of Technology.
    Gevorgian, S
    Chalmers University of Technology.
    Cho, C.-R
    Royal Institute of Technology.
    Grishin, A.
    Royal Institute of Technology.
    Andreasson, Johanna
    Lindbäck, Ture
    DC field dependent properties of Na0.5K0.5NbO₃/SiO₂/Si structures at millimeter-wave frequencies2001In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 78, no 13, p. 1900-1902Article in journal (Refereed)
    Abstract [en]

    Dielectric properties of laser-ablated 0.5-μm-thick c-axis epitaxial Na0.5K0.5NbO3 films on high-resistivity (7.7 Ω cm) silicon SiO2/Si substrate are studied experimentally at frequencies up to 40 GHz. For measurements, planar 0.5-μm-thick gold electrodes (interdigital and straight slot) are photolithography defined on the top surface of Na0.5K0.5NbO3 films. The slot width between the electrodes is 2 or 4 μm. 13% capacitance change at 40 V dc bias and Q factor more than 15 are observed at 40 GHz, which makes the structure useful for applications in electrically tunable millimeter-wave devices

  • 17.
    Abadei, S.
    et al.
    Chalmers University of Technology, Department of Microelectronics.
    Gevorgian, S.
    Chalmers University of Technology, Department of Microelectronics.
    Kugler, V.
    Department of Physics, Linköping University.
    Helmersson, U.
    Department of Physics, Linköping University.
    Andreasson, Johanna
    Luleå University of Technology, Department of Engineering Sciences and Mathematics.
    Microwave properties of tunable capacitors basee on magnetron sputtered ferroelectric Na0.5K0.5NbO3 film on low and high resistivity silicon substrates2001In: Integrated Ferroelectrics, ISSN 1058-4587, E-ISSN 1607-8489, Vol. 39, no 1-4, p. 359-366Article in journal (Refereed)
    Abstract [en]

    In this work, small signal DC voltage dependent dielectric permittivity, loss tangent, and tuneability of magnetron sputtered epitaxial Na0.5K0.5NO3 films are studied experimentally. (100)-oriented Na0.5K0.5NbO3 films are deposited onto SiO2-buffered CMOS grade low resistivity (p = 10-20 cm) and high resistivity (p = 15-45 kcm) silicon substrates. Planar capacitors with 2 or 4 m gaps between electrodes have been fabricated on top of ferroelectric films. These devices have been characterized in the frequency range 1.0 MHz to 50 GHz at temperatures 30 - 300K. Na0.5K0.5NbO3/SiO2/Si structures on high resistivity silicon substrate exhibit C-V performances typical for Metal-Insulator- Semiconductor (MIS) capacitors. At low frequencies, f 1.0 GHz, the large tuneability and large losses are associated with the MIS structure, while at higher microwave frequencies the tuneability is mainly associated with the ferroelectric, film. At 1.0 MHz and room temperature, the tuneability of Na0.5K0.5NbO3/SiO2/Si structures more than 90%, reducing to 10-15 % at 50 GHz. The losses decrease with increasing the DC bias and frequency. A Q-factor more than 15 at 50 GHz is observed. The dielectric permittivity of the Na0.5K0.5NbO3 film is in the range 50-150 at frequencies 0.045-50 GHz. On low resistivity substrate the performance of Na0.5K0.5NbO3 films is completely screened by the high losses in silicon, and the tuneability is negligible

  • 18.
    Abbas, Nahla
    et al.
    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.
    Wasimi, Saleh
    School of Engineering & Technology, Central Queensland University, Melbourne, Australia.
    Al-Rawabdeh, Abdulla M.
    Department of Earth and Environmental Science, Yarmouk University, Irbid, Jordan.
    Flow Variation of the Major Tributaries of Tigris River Due to Climate Change2019In: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 11, no 8, p. 437-442Article in journal (Refereed)
    Abstract [en]

    Iraq relies greatly  on  the  flow of  the  Euphrates  and  Tigris Rivers  and  their tributaries. Five tributaries namely Khabour, Greater Zab, Lesser Zab, AlAd- hiam  and  Daylia,  which  are  the  major  tributaries  of  Tigris  River,  sustain Northern  Iraq  Region,  a  semi-arid,  mainly  a  pastureland.  These  tributaries contribute about 24 km3  of water annually. The discharge in the tributaries, in recent  times,  has  been  suffering  increasing  variability  contributing  to  more severe droughts and floods apparently due to climate change. This is because there were no dams constructed outside Iraq previously. For an appropriate appreciation,  Soil  Water  Assessment Tool  (SWAT)  model  was used  to evaluate  the  impact  of  climate  change  on  their  discharge  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 that wa-ter resources are expected to decrease with time.

  • 19.
    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.

  • 20.
    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.

  • 21.
    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.

  • 22.
    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.

  • 23.
    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.

  • 24.
    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.

  • 25.
    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.

  • 26.
    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.

  • 27.
    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.

  • 28.
    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.

  • 29.
    Abdelaziz, Ahmed
    et al.
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Ang, Tanfong
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Sookhak, Mehdi
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Khan, Suleman
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Liew, Cheesun
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Akhunzada, Adnan
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Survey on network virtualization using openflow: Taxonomy, opportunities, and open issues2016In: KSII Transactions on Internet and Information Systems, ISSN 1976-7277, Vol. 10, no 10, p. 4902-4932Article in journal (Refereed)
    Abstract [en]

    The popularity of network virtualization has recently regained considerable momentum because of the emergence of OpenFlow technology. It is essentially decouples a data plane from a control plane and promotes hardware programmability. Subsequently, OpenFlow facilitates the implementation of network virtualization. This study aims to provide an overview of different approaches to create a virtual network using OpenFlow technology. The paper also presents the OpenFlow components to compare conventional network architecture with OpenFlow network architecture, particularly in terms of the virtualization. A thematic OpenFlow network virtualization taxonomy is devised to categorize network virtualization approaches. Several testbeds that support OpenFlow network virtualization are discussed with case studies to show the capabilities of OpenFlow virtualization. Moreover, the advantages of popular OpenFlow controllers that are designed to enhance network virtualization is compared and analyzed. Finally, we present key research challenges that mainly focus on security, scalability, reliability, isolation, and monitoring in the OpenFlow virtual environment. Numerous potential directions to tackle the problems related to OpenFlow network virtualization are likewise discussed

  • 30.
    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

  • 31.
    Abd-Ellah, Mahmoud Khaled
    et al.
    Al-Madina Higher Institute for Engineering and Technology.
    Awad, Ali Ismail
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Khalaf, Ashraf A. M.
    Minia University, Egypt.
    Hamed, Hesham F. A.
    Minia University, Egypt.
    Classification of Brain Tumor MRIs Using a Kernel Support Vector Machine2016In: Building Sustainable Health Ecosystems: 6th International Conference on Well-Being in the Information Society, WIS 2016, Tampere, Finland, September 16-18, 2016, Proceedings / [ed] Hongxiu Li, Pirkko Nykänen, Reima Suomi, Nilmini Wickramasinghe, Gunilla Widén, Ming Zhan, Springer International Publishing , 2016, p. 151-160Conference paper (Refereed)
    Abstract [en]

    The use of medical images has been continuously increasing, which makes manual investigations of every image a difficult task. This study focuses on classifying brain magnetic resonance images (MRIs) as normal, where a brain tumor is absent, or as abnormal, where a brain tumor is present. A hybrid intelligent system for automatic brain tumor detection and MRI classification is proposed. This system assists radiologists in interpreting the MRIs, improves the brain tumor diagnostic accuracy, and directs the focus toward the abnormal images only. The proposed computer-aided diagnosis (CAD) system consists of five steps: MRI preprocessing to remove the background noise, image segmentation by combining Otsu binarization and K-means clustering, feature extraction using the discrete wavelet transform (DWT) approach, and dimensionality reduction of the features by applying the principal component analysis (PCA) method. The major features were submitted to a kernel support vector machine (KSVM) for performing the MRI classification. The performance evaluation of the proposed system measured a maximum classification accuracy of 100 % using an available MRIs database. The processing time for all processes was recorded as 1.23 seconds. The obtained results have demonstrated the superiority of the proposed system.

  • 32.
    Abd-Ellah, Mahmoud Khaled
    et al.
    Electronic and Communication Department Al-Madina Higher Institute for Engineering and Technology, Giza.
    Awad, Ali Ismail
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Khalaf, Ashraf A. M.
    Faculty of Engineering, Minia University.
    Hamed, Hesham F. A.
    Faculty of Engineering, Minia University.
    Design and implementation of a computer-aided diagnosis system for brain tumor classification2017In: 2016 28th International Conference on Microelectronics (ICM), 2017, p. 73-76, article id 7847911Conference paper (Refereed)
    Abstract [en]

    Computer-aided diagnosis (CAD) systems have become very important for the medical diagnosis of brain tumors. The systems improve the diagnostic accuracy and reduce the required time. In this paper, a two-stage CAD system has been developed for automatic detection and classification of brain tumor through magnetic resonance images (MRIs). In the first stage, the system classifies brain tumor MRI into normal and abnormal images. In the second stage, the type of tumor is classified as benign (Noncancerous) or malignant (Cancerous) from the abnormal MRIs. The proposed CAD ensembles the following computational methods: MRI image segmentation by K-means clustering, feature extraction using discrete wavelet transform (DWT), feature reduction by applying principal component analysis (PCA). The two-stage classification has been conducted using a support vector machine (SVM). Performance evaluation of the proposed CAD has achieved promising results using a non-standard MRIs database.

  • 33.
    Abd-Ellah, Mahmoud Khaled
    et al.
    Electronics and Communications Department, Al-Madina Higher Institute for Engineering and Technology, Giza, Egypt.
    Awad, Ali Ismail
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. Faculty of Engineering, Al-Azhar University, Qena, Egypt.
    Khalaf, Ashraf A.M.
    Electronics and Communications Department, Faculty of Engineering, Minia University, Minia, Egypt.
    Hamed, Hesham F.A.
    Electronics and Communications Department, Faculty of Engineering, Minia University, Minia, Egypt.
    A Review on Brain Tumor Diagnosis from MRI Images: Practical Implications, Key Achievements, and Lessons Learned2019In: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 61, p. 300-318Article in journal (Refereed)
    Abstract [en]

    The successful early diagnosis of brain tumors plays a major role in improving the treatment outcomes and thus improving patient survival. Manually evaluating the numerous magnetic resonance imaging (MRI) images produced routinely in the clinic is a difficult process. Thus, there is a crucial need for computer-aided methods with better accuracy for early tumor diagnosis. Computer-aided brain tumor diagnosis from MRI images consists of tumor detection, segmentation, and classification processes. Over the past few years, many studies have focused on traditional or classical machine learning techniques for brain tumor diagnosis. Recently, interest has developed in using deep learning techniques for diagnosing brain tumors with better accuracy and robustness. This study presents a comprehensive review of traditional machine learning techniques and evolving deep learning techniques for brain tumor diagnosis. This review paper identifies the key achievements reflected in the performance measurement metrics of the applied algorithms in the three diagnosis processes. In addition, this study discusses the key findings and draws attention to the lessons learned as a roadmap for future research.

  • 34.
    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, Benaha.
    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.

  • 35.
    Abdikalikova, Zamira
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Compactness of embedding between Sobolev type spaces with multiweighted derivatives2009In: AIHT : Analysis, Inequalities and Homogenization Theory: Midnight sun conference in honor of Lars-Erik Persson, 2009Conference paper (Other academic)
    Abstract [en]

    We consider a new Sobolev type function space called the space with multiweighted derivatives. As basis for this space serves some differential operators containing weight functions. We establish necessary and sufficient conditions for the boundedness and compactness of the embedding between the spaces with multiweighted derivatives in different selections of weights.

  • 36.
    Abdikalikova, Zamira
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Embedding theorems for spaces with multiweighted derivatives2007Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This Licentiate Thesis consists of four chapters, which deal with a new Sobolev type function space called the space with multiweighted derivatives. This space is a generalization of the usual one dimensional Sobolev space. Chapter 1 is an introduction, where, in particular, the importance to study function spaces with weights is discussed and motivated. In Chapter 2 we consider and analyze some results of L. D. Kudryavtsev, where he investigated one dimensional Sobolev spaces. Moreover, in this chapter we present and prove analogous results by B. L. Baidel'dinov for generalized Sobolev spaces. These results are crucially for the proofs of the main results of this Licentiate Thesis. In Chapter 3 we prove some embedding theorems for these new generalized Sobolev spaces. The main results of Kudryavtsev and Baidel'dinov about characterization of the behavior of functions at a singularity take place in weak degeneration of spaces. However, with the help of our new embedding theorems we can extend these results to the case of strong degeneration. In Chapter 4 we prove some new estimates for each function in a Tchebychev system. In order to be able to study also compactness of the embeddings from Chapter 3 such estimates are crucial. I plan to study this question in detail in my further PhD studies.

  • 37.
    Abdikalikova, Zamira
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Some new results concerning boundedness and compactness for embeddings between spaces with multiweighted derivatives2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This Doctoral Thesis consists of five chapters, which deal with a new Sobolev type function space called the space with multiweighted derivatives. This space is a generalization of the usual one dimensional Sobolev space. As basis for this space serves some differential operators containing weight functions.Chapter 1 is an introduction, where, in particular, the importance to study function spaces with weights is discussed and motivated. In Chapter 2 we prove some new estimates for each function in a Tchebychev system. In order to be able to study compactness of the embeddings from Chapter 3 such estimates are crucial.In Chapter 3 we rewrite and present some results of L. D. Kudryavtsev, where he investigated one dimensional Sobolev spaces. Moreover, in this chapter we rewrite and discuss some analogous results by B. L. Baidel'dinov for generalized Sobolev spaces. These results are not available in the Western literatures in this way and they are crucial for the proofs of the main results in Chapter 4. In Chapter 4 we prove some embedding theorems for these new generalized Sobolev spaces. The main results of Kudryavtsev and Baidel'dinov about characterization of the behavior of functions at a singularity take place in weak degeneration of the spaces. However, with the help of our new embedding theorems we can extend theseresults to the case of strong degeneration.The main aim of Chapter 5 is to establish boundedness and compactness of the embedding considered in Chapter 4.In Chapter 4 basically only sufficient conditions for boundedness of this embedding were obtained. In Chapter 5 we obtain necessary and sufficient conditions for boundedness and compactness of this embedding and the main results are proved in a different way.

  • 38. Abdikalikova, Zamira
    et al.
    Baiarystanov, Askar O.
    Oinarov, Ryskul
    Compactness of embedding between spaces with multiweighted derivatives: the case 1 ≤ p ≤ q2009Report (Other academic)
  • 39.
    Abdikalikova, Zamira
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Kalybay, Aigerim
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Summability of a Tchebysheff system of functions2007Report (Other academic)
  • 40.
    Abdikalikova, Zamira
    et al.
    L.N. Gumilyov Eurasian National University.
    Oinarov, Ryskul
    L.N. Gumilyov Eurasian National University.
    Persson, Lars-Erik
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Boundedness and compactness of the embedding between spaces with multiweighted derivatives when 12011In: Czechoslovak Mathematical Journal, ISSN 0011-4642, E-ISSN 1572-9141, Vol. 61, no 1, p. 7-26Article in journal (Refereed)
    Abstract [en]

    We consider a new Sobolev type function space called the space with multiweighted derivatives W-p(n),(alpha) over bar, where (alpha) over bar = (alpha(0), alpha(1), ......, alpha(n)), alpha(i) is an element of R, i = 0, 1,......,n, and parallel to f parallel to W-p(n),((alpha) over bar) = parallel to D((alpha) over bar)(n)f parallel to(p) + Sigma(n-1) (i=0) vertical bar D((alpha) over bar)(i)f(1)vertical bar, D((alpha) over bar)(0)f(t) = t(alpha 0) f(t), d((alpha) over bar)(i)f(t) = t(alpha i) d/dt D-(alpha) over bar(i-1) f(t), i = 1, 2, ....., n. We establish necessary and sufficient conditions for the boundedness and compactness of the embedding W-p,(alpha) over bar(n) -> W-q,(beta) over bar,(m) when 1 <= q < p < infinity, 0 <= m < n

  • 41.
    Abdikalikova, Zamira
    et al.
    L.N. Gumilyov Eurasian National University.
    Oinarov, Ryskul
    L.N. Gumilyov Eurasian National University.
    Persson, Lars-Erik
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Boundedness and compactness of the embedding between spaces with multiweighted derivatives when 1≤ q2009Report (Other academic)
  • 42.
    Abdollahpour, N.
    et al.
    Department of Ergonomics, University of Social Welfare and Rehabilitation Science, Tehran.
    Helali, Faramarz
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Hoseini, M.A.
    Department of Rehabilitation Management, University of Social Welfare and Rehabilitation Science, Tehran.
    Ghomshe, F. Tabatabaei
    Department of Industrial Engineering, Institute for Higher Education of Kar, Qhazvin.
    Ziarani, M. Hamzeiyan
    Department of Industrial Engineering, Institute for Higher Education of Kar, Qhazvin.
    Peysepar, S.
    HSE Unit of MAPNA Turbine Blade Engineering and Manufacturing Company-PARTO, Karaj.
    An improving working condition system (health, safety and ergonomics) survey and analysis with macroergonomics approach in a manufacturing company from Iran Power Plant Industry in 20102013In: Iran Occupational Health, ISSN 1735-5133, E-ISSN 2228-7493, Vol. 10, no 4, p. 55-64Article in journal (Refereed)
    Abstract [en]

    Background and aims: World experience has shown the positive effect of applying ergonomics in improving work conditions, of quality and quantity of production, reducing prevalence of work-related musculoskeletal disorders, saving costs and increase of productivity in the different contents. These are possible only with utilizing properly improving work condition system and Macroergonomics approach. The aim of the study was how determine situation and analyzing the working conditions using the macroergonomics approach in a Power Plant Industry. Methods: This study is a cross-sectional study. First, the program for improvement of work conditions were evaluated using three questionnaires including managers viewpoint (29 samples), health, safety and environment employees viewpoint (5 samples) and operating workers viewpoint (85 samples) and then three other instruments of macroergonomics were used. Results: According to the results of 1) questionnaires and corresponding tests, three of the program's goals of improving working conditions and promotion practices that have the same opinions, but in some cases had different opinions. 2) Future workshops and interviews, the lack of participatory leadership and lack of collaborative work systems for the company stated. 3) Apply ergonomics checklist of ILO, an appropriate interaction between the top and bottom surfaces revealed. Conclusion: Awakened needs of change in the middle and lower levels of organization to solve problems relate to improving working conditions of the system was created. To implement an Ergonomics Intervention Programme Technique Process requires the full support management and employees.

  • 43.
    Abdollahpour, Nosrat
    et al.
    Department of Occupational Health, School of Health, Tabriz University of Medical Sciences, Tabriz.
    Dastranj, Farahnaz
    Occupational Health, International Campus of Shahid Sadoughi University of Medical Sciences (IC-SSUMS) Yazd – Iran.
    Helali, Faramarz
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Ziarani, M. Hamzeian
    Zeiaei, M.
    Stress Prevention at Work Checkpoints: Practical improvements for stress prevention the workplace2016 (ed. Free)Book (Other (popular science, discussion, etc.))
  • 44.
    Abdollahpour, Nosrat
    et al.
    Department of Occupational Health Engineering, Tabriz University of Medical Sciences Tabriz, Iran.
    Helali, Faramarz
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Implementing 'Awakened Need of Change' for Applying Ergonomics to Work System with Macroergonomics Approach in an Industrially Derveloping Country and its Meta-Reflection2016In: Journal of Ergonomics, ISSN 2165-7556, Vol. 6, no 6, article id 182Article in journal (Refereed)
  • 45.
    Abdollahpour, Nosrat
    et al.
    Department of Occupational Health, School of Health, Ardabil University of Medical Sciences, Ardabil.
    Helali, Faramarz
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Human Work Science.
    Ziaei, M
    Department of Occupational Health, School of Health, Shiraz University of Medical Sciences, Shiraz.
    Hamzeian, M
    Department of Ergonomics, University of Social Welfare and Rehabilitation Science, Tehran.
    Keikhamoghadam, AA
    Department of Occupational Health, School of Health, Tabriz University of Medical Sciences, Tabriz.
    Gholamnia, R
    Department of Occupational Health Engineering, School of Health, Safety and environment, Shahid Beheshti University of Medical Sciences, Tehran.
    Ghaffari, A
    HSE Unit of National Iranian Gas Company, Tehran, Iran.
    Assessment of risk factors and the prevalence of musculoskeletal disorders by QEC and Body Map operational units of the gas refinery in Iran and its Meta-Reflection2016In: Journal of Heath, ISSN 2382-9710, Vol. 7, no 1, p. 35-50, article id 7Article in journal (Refereed)
    Abstract [en]

    Introduction: This study aims to evaluate the risk factors and the prevalence of WMSDs disorders using QEC and Body Map techniques in operational units took a gas refineries and its Meta-Reflection.Method and Material: This case study assessed 254 operators in three distinct phases. First, 72 workstation posture was evaluated by using of QEC. Secondly was intended for employees of WMSDs were assessed using by Body Map. After conducting interview with relevant directors, the effectiveness of such studies has been analyzed through Meta-Reflection.Results: Based on results came from QEC survey, the operators’ average scores was %53/8. Moreover, results of Body Map assessment showed that the highest organs of WMSDs were back and knee extrusions (47% and 46% respectively). Also, lack of ergonomics policy and plan within refinery has demonstrated by interviews. Meta-Reflection, on the other hand, showed that because of incomplete learning cycles in the mentioned surveys which only provide WMSDs’ status, workstations’ ergonomics condition, and introduce expert based solutions. Thus, such surveys not only have incomplete study plan, but also have less impact on improving overall health, safety and ergonomics within this organization.Conclusion: This research proves that non-ergonomic conditions result in awkward postures and subsequent physical disorders. Overall, this study has showed a gap from this kind of the work on the learning cycles at organizational levels, a trend should be considered to interactive research work on the workplaces with improved and promoted system ergonomics attitude.

  • 46.
    Abdulbaqi, Dana M.
    et al.
    Saudi Aramco, Dhahran.
    Dahl, Carol
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences. Mineral and Energy Economics Program and Payne Institute of Earth Resources, Division of Economics and Business, Colorado School of Mines, Golden, CO .
    Al-Shaikh, Mohammed
    Saudi Aramco, Dhahran.
    Enhanced Oil Recovery (EOR) as a Stepping Stone to Carbon Capture and Sequestration (CCS)2018In: Mineral Economics, ISSN 2191-2203, E-ISSN 2191-2211, Vol. 31, no 1-2, p. 239-251Article in journal (Refereed)
    Abstract [en]

    Environmental concerns about carbon emissions coupled with the oil industry’s need to secure additional CO2 for enhanced oil recovery (CO2-EOR) projects have sparked interest in the potential that CO2-EOR may have in jumpstarting carbon capture and sequestration (CCS). However, existing studies on the viability of coupling CO2-EOR with CCS have generally placed more focus on either the engineering or economic aspects of the problem. Most engineering studies focus on the technical aspects of the CO2-EOR project to produce the maximum amount of oil, while simultaneously storing the most CO2 during the production process with the economics as an afterthought, while most economic studies found have focused on a singular aspect of the issue such as impacts of exogenously varying injection rates. Furthermore, modelling efforts have stopped at the end of the productive life of the field. We build a unique two-stage dynamic optimization model, which simultaneously addresses engineering and economic policy aspects, to study the viability of coupling CO2-EOR transitioning into CCS. Our model includes a carbon tax for emissions, which becomes a subsidy for full scale sequestration after oil production has ceased; this allows us to explore the transition from CO2-EOR, our first stage, to sole CO2 sequestration in our second stage for a single field. We maximize the operator’s profits across both stages, while tracking the responsiveness of oil production and total carbon movements to both price and policy changes. We pair our optimization model with a reservoir simulation model, allowing us to mimic actual field behavior, giving our work a more realistic representation of both production and sequestration profiles. Our results suggest that small increases in the level of carbon tax can have large and discontinuous impacts on net sequestration. This stems from the observed transition from limited natural sources of CO2 to more expensive captured CO2 resulting from the implemented policy. With appropriate taxes, total volumes of captured CO2 sequestered across both stages are equivalent to 30 to 40% of the emissions from the use of the oil produced. With the credits oil producers receive from sequestering CO2, which equate to the tax, relatively high carbon taxes incentivize additional sequestration without significantly impacting the supply of oil. This, alongside maintaining a steady stream of profits, is a win-win situation for energy security and the climate.

  • 47.
    Abdul-Jalbar, Beatriz
    et al.
    Dpto. de Matemáticas, Estadística e Investigación Operativa, Universidad de La Laguna, Spain.
    Segerstedt, Anders
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    A note on “A new heuristic for one warehouse and N retailers problem” by Ercan Senyigit and Hakan Akkan in Procedia - Social and Behavioral Sciences, 62, p. 656 – 660, 20122019Manuscript (preprint) (Other academic)
  • 48.
    Abdul-Jalbar, Beatriz
    et al.
    Universidad de La Laguna.
    Segerstedt, Anders
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Sicilia, Joaquín
    Universidad de La Laguna.
    Nilsson, Andreas
    A new heuristic to solve the one-warehouse N-retailer problem2010In: Computers & Operations Research, ISSN 0305-0548, E-ISSN 1873-765X, Vol. 37, no 2, p. 265-272Article in journal (Refereed)
    Abstract [en]

    We deal with a multi-echelon inventory system in which one warehouse supplies an item to multiple retailers. Customer demand arrives at each retailer at a constant rate. The retailers replenish their inventories from the warehouse that in turn orders from an outside supplier. It is assumed that shortages are not allowed and lead times are negligible. The goal is to determine replenishment policies that minimize the overall cost in the system. We develop a heuristic to compute efficient policies, which also can easily be used in a spreadsheet application. The main idea consists of finding a balance between the replenishment and the inventory holding costs at each installation. This new heuristic we compare with two other approaches proposed in the literature; the computational studies show that in most of the instances generated the new method provides lower costs.

  • 49.
    Abdullah, M Ailieen
    et al.
    Royal Institute of Technology, Stockholm.
    Rönnbäck, Anna Öhrwall
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell marknadsföring och industriell ekonomi.
    Sandström, Gunilla Ölundh
    Royal Institute of Technology.
    Building Networks for Delivering Integrated Product-Service Offerings (IPSOs)2010In: Industrial product-service systems -IPS²: proceedings of the 2nd CIRP IPS² Conference [2010, Linköping, 14-15 April], Linköping, 2010Conference paper (Refereed)
    Abstract [en]

    The paper describes the effect of forming business networks and collaborations for the purpose of developing an Integrated Product-Service Offering (IPSO) using the Product/Service Systems (PSS). The research method is an in-depth case study of a joint venture formed by four companies developing a new technology for chemical extraction from water sludge waste within the pulp and paper industry.Combining literature from PSS, network theories and collaborative product development, this paper puts forward the benefits for SMEs to collaborate in business networks and produce IPSOs when introducing a new technology in an emerging market. The case study shows that working towards the new market would not have been possible if each party acted individually or maintained their traditional buyer-supplieroperator roles, and that IPSOs can reduce the business risk.

  • 50.
    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)
1234567 1 - 50 of 43708
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf