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  • 51.
    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

  • 52.
    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

  • 53.
    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.

  • 54.
    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.

  • 55.
    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.

  • 56.
    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.

  • 57.
    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.

  • 58.
    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.

  • 59.
    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.

  • 60. Abdikalikova, Zamira
    et al.
    Baiarystanov, Askar O.
    Oinarov, Ryskul
    Compactness of embedding between spaces with multiweighted derivatives: the case 1 ≤ p ≤ q2009Report (Other academic)
  • 61.
    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)
  • 62.
    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

  • 63.
    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)
  • 64. Abdo, Eli
    Komplexiteten bakom masken: En kvalitativ studie om intagna ungdomars rolltagande2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 65. Abdollahi, Golrou
    Creating a model for customer loyalty in banking industry of Iran2008Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The customer loyalty concept has received much attention from both academics and practitioners in different industry. Banking industry is also not excluded and because it has a highly interaction with the customers, getting familiar with this concept would be very important and helpful for managers in defining strategies. So this research attempts to find the customer loyalty factors and their relationships with banking industry in one of the developing countries in order to provide a model for this concept. In order to do this a questionnaire is designed and validated ,then based on the data which were gained from the 400 respondents’ answers to the designed questionnaire, the analysis is done on and the results and the relations are explained. Satisfaction, choosing, habit, tangible and intangible service quality and switching cost are the factors which influence the loyalty factor. To analyze the data, SPSS and LISREL software were used. It is hoped that this Master thesis would be helpful and interesting for both academics and practitioners.

  • 66.
    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.

  • 67.
    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.))
  • 68.
    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)
  • 69.
    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.

  • 70.
    Abdukalikova, Anara
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Machine Learning assisted system for the resource-constrained atrial fibrillation detection from short single-lead ECG signals2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    An integration of ICT advances into a conventional healthcare system is spreading extensively nowadays. This trend is known as Electronic health or E-Health. E-Health solutions help to achieve the sustainability goal of increasing the expected lifetime while improving the quality of life by providing a constant healthcare monitoring. Cardiovascular diseases are one of the main killers yearly causing approximately 17.7 million deaths worldwide. The focus of this work is on studying the detection of one of the cardiovascular diseases – Atrial Fibrillation (AF) arrhythmia.  This type of arrhythmia has a severe influence on the heart health conditions and could cause congestive heart failure (CHF), stroke, and even increase the risk of death. Therefore, it is important to detect AF as early as possible. In this thesis we focused on studying various machine learning techniques for AF detection using only short single lead Electrocardiography recordings. A web-based solution was built as a final prototype, which first simulates the reception of a recorded signal, conducts the preprocessing, makes a prediction of the AF presence, and visualizes the result. For the AF detection the relatively high accuracy score was achieved comparable to the one of the state-of-the-art. The work was based on the investigation of the proposed architectures and the usage of the database of signals from the 2017 PhysioNet/CinC Challenge. However, an additional constraint was introduced to the original problem formulation, since the idea of a future deployment on the resource-limited devices places the restrictions on the complexity of the computations being performed for achieving the prediction. Therefore, this constraint was considered during the development phase of the project.

  • 71. Abdulal, Katrin
    et al.
    Vendelson, Henrik
    Telemedicin för effektivare informationsutbyte inom äldrevården: en fallstudie av en telemedicinsk tillämpning mellan kommun och landsting i Arvidsjaurs kommun2001Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 72.
    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.

  • 73. Abdulhussein, Muthanna
    QoS of Mobile Broadband Users in Heterogeneous Networks2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Initial deployments of LTE networks are based on so called homogeneous networks consisting of only Macro base stations for basic coverage. As the number of users increases, especially in densely populated areas, the macro base stations are believed to lack sufficient capacity to bear the load of traffic increase for mobile broadband users. To overcome this problem the macro network will be complemented with low power nodes, such as Pico and Femto eNBs, will improve the system capacity.This Master thesis study comprises an investigation on how quality of service can be maintained for video telephony users in heterogeneous networks when considering different configurations, user patterns, user distributions, and user loads.Three heterogeneous configurations specified by 3GPP were compared to a reference case; a pure macro network. Firstly, the simulation results show that when introducing low power nodes (LPN), the video telephony capacity increases with the increase in the number of users clustered around the hot-spots for all configurations. Also, in the heterogeneous network users in the macro cells experience slightly lower interference when more users are absorbed by the low power nodes. The video telephony tail latency experiences a sharp increase for all configurations. The reason for this is that the worst cells become congested and the users will compete for the available resources. It is observed that the tail latency in uplink, already at low load, is higher than in downlink due to that the scheduler is located at eNodeB.Secondly, a scenario investigating the gain of Low power nodes range extension showed that signal to interference and noise ratio (SINR) problems arise if the range of the low power nodes is extended, however the system as a whole observes increased throughput. The main reasons are macro layer offloading and reduced interference created by the macro layer. Finally, a scenario investigating the addition of multiple Low power nodes cells with range extension showed that video telephony capacity will be further improved when multiple Low power nodes are combined with range-extension.The combination of range extension and multiple low power nodes (LPN) will reduce the interference originating from the macro cells as a result of the offloading of the macro cells. This since more users will be served by the LPN cells. As a result, the macro physical resource block utilization will be reduced. It was shown also that the throughput of the LPN cells is not related to the number of deployed LPNs, but it depends on the size of the LPN cell increase of RSRP offset.

  • 74.
    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.

  • 75.
    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.

  • 76.
    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)
  • 77.
    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.

  • 78.
    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.

  • 79.
    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.

  • 80.
    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.

  • 81.
    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.

  • 82.
    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.

  • 83.
    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.

  • 84.
    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.

  • 85.
    Abdullah, Twana
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering. Groundwater Directorate of Sulaimani, Kurdistan,Iraq.
    Ali, Salahalddin S.
    Department of Geology, University of Sulaimani,Kurdistan, Iraq. Komar University of Science and Technology, Iraqi Kurdistan , Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Knutsson, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Hydrogeochemical Evaluation of Groundwater and Its Suitability for Domestic Uses in Halabja Saidsadiq Basin, Iraq2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 4, article id 690Article in journal (Refereed)
    Abstract [en]

    Evaluation of the hydrogeochemical characteristics and groundwater suitability for domestic use was conducted in the Halabja Saidsadiq Basin in the northeastern part of Iraq. The total studied area is about 1278 km 2 with a specific Mediterranean-type continental interior climate, which is cold in winter and hot in summer. To conduct the required laboratory chemical analysis for groundwater samples in the studied basin, 78 groundwater samples, in total, were collected from 39 water wells in the dry and wet seasons in 2014 and analyzed for major cations and anions, and the results were compared with the permitted limits for drinking water. An examination of the chemical concentrations of the World Health Organization drinking water norms demonstrate that a large portion of the groundwater samples is suitable for drinking, and a preponderance of groundwater samples situated in the class of hard and very hard water types for both seasons. Suitability of groundwater for drinking use was additionally assessed according to the water quality index classification. This showed that more than 98% of groundwater samples have good water quality in the dry and wet seasons. Conversely, the classification of groundwater samples based on Piper’s diagram designates that the groundwater type is alkaline water, with existing bicarbonate along with sulfate and chloride. However, water–ock exchange processes and groundwater flow have been responsible for the dominant water type of Ca–g–CO3.

  • 86.
    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.

  • 87.
    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.

  • 88. Abedelbari, Shereen
    Elektrisk stimulerings effekt på post-stroke spasticitet och motorfunktion2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 89. Abedi, Ali
    A study of appropriateness of information system development approach in preliminary investigation phase2002Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With the existence of over a 1000 different Information System Development Methodologies (ISDM). Given the effort directed to development of ISDMs one would expect a lively discussion on how to select methodologies in practice and how to catalogue them as a perquisite to study the merits of various features and identify the most useful ones per project situation. However neither seems the case. One serious deficiency in Information Systems management is the lack of recognition that different projects require different managerial approaches. Although, there are enormous methodologies/design approaches in academic world and business world usually they can be grouped based on certain common characteristics. This research examines the relationship between information systems development methods and the characteristics of the domain in which they are used and the organizational policy regarding development approach adoption and adaptation per project. The fundamental theme in this research is based on a simple question of “how developer makes an informed choice for the selection of preferred Information System Development Approach (ISDA) by considering project characteristics?” The main proposition in this research is: cognition of complexity, uncertainty and formality of the work context will narrow down the choices to groups of approaches based on their two important characteristics namely mode of operation and means of expression. To examine and answer the research questions, a large-scale online survey was carried out targeted at companies with direct systems development exposure. Utilizing the theory and data retrieved from the survey, findings of the research is that adoption of information systems development approach based on project characteristics has a higher success rate compared to those not adopted in regards to project characteristics. The other finding is that cognition of project degree of complexity and uncertainty is necessary but not sufficient for making the adoption choice. In other words: non-project factors such as management of the approach and the risk associated with the approach should be taken into consideration in addition to the project characteristics for that matter.

  • 90.
    Abedin, Md. Zainal
    et al.
    University of Science and Technology Chittagong.
    Chowdhury, Abu Sayeed
    University of Science and Technology Chittagong.
    Hossain, Mohammad Shahadat
    University of Chittagong, Bangladesh.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Karim, Razuan
    University of Science and Technology Chittagong.
    An Interoperable IP based WSN for Smart Irrigation Systems2017Conference paper (Refereed)
    Abstract [en]

    Wireless Sensor Networks (WSN) have been highly developed which can be used in agriculture to enable optimal irrigation scheduling. Since there is an absence of widely used available methods to support effective agriculture practice in different weather conditions, WSN technology can be used to optimise irrigation in the crop fields. This paper presents architecture of an irrigation system by incorporating interoperable IP based WSN, which uses the protocol stacks and standard of the Internet of Things paradigm. The performance of fundamental issues of this network is emulated in Tmote Sky for 6LoWPAN over IEEE 802.15.4 radio link using the Contiki OS and the Cooja simulator. The simulated results of the performance of the WSN architecture presents the Round Trip Time (RTT) as well as the packet loss of different packet size. In addition, the average power consumption and the radio duty cycle of the sensors are studied. This will facilitate the deployment of a scalable and interoperable multi hop WSN, positioning of border router and to manage power consumption of the sensors.

  • 91.
    Abedin, Md. Zainal
    et al.
    University of Science and Technology, Chittagong.
    Paul, Sukanta
    University of Science and Technology, Chittagong.
    Akhter, Sharmin
    University of Science and Technology, Chittagong.
    Siddiquee, Kazy Noor E Alam
    University of Science and Technology, Chittagong.
    Hossain, Mohammad Shahadat
    University of Chittagong, Bangladesh.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Selection of Energy Efficient Routing Protocol for Irrigation Enabled by Wireless Sensor Networks2017In: Proceedings of 2017 IEEE 42nd Conference on Local Computer Networks Workshops, Piscataway, NJ: Institute of Electrical and Electronics Engineers (IEEE), 2017, p. 75-81Conference paper (Refereed)
    Abstract [en]

    Wireless Sensor Networks (WSNs) are playing remarkable contribution in real time decision making by actuating the surroundings of environment. As a consequence, the contemporary agriculture is now using WSNs technology for better crop production, such as irrigation scheduling based on moisture level data sensed by the sensors. Since WSNs are deployed in constraints environments, the life time of sensors is very crucial for normal operation of the networks. In this regard routing protocol is a prime factor for the prolonged life time of sensors. This research focuses the performances analysis of some clustering based routing protocols to select the best routing protocol. Four algorithms are considered, namely Low Energy Adaptive Clustering Hierarchy (LEACH), Threshold Sensitive Energy Efficient sensor Network (TEEN), Stable Election Protocol (SEP) and Energy Aware Multi Hop Multi Path (EAMMH). The simulation is carried out in Matlab framework by using the mathematical models of those algortihms in heterogeneous environment. The performance metrics which are considered are stability period, network lifetime, number of dead nodes per round, number of cluster heads (CH) per round, throughput and average residual energy of node. The experimental results illustrate that TEEN provides greater stable region and lifetime than the others while SEP ensures more througput.

  • 92.
    Abedin, Md. Zainal
    et al.
    University of Science and Technology, Chittagong.
    Siddiquee, Kazy Noor E Alam
    University of Science and Technology Chittagong.
    Bhuyan, M. S.
    University of Science & Technology Chittagong.
    Karim, Razuan
    University of Science and Technology Chittagong.
    Hossain, Mohammad Shahadat
    University of Chittagong, Bangladesh.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Performance Analysis of Anomaly Based Network Intrusion Detection Systems2018In: Proveedings of the 43nd IEEE Conference on Local Computer Networks Workshops (LCN Workshops), Piscataway, NJ: IEEE Computer Society, 2018, p. 1-7Conference paper (Refereed)
    Abstract [en]

    Because of the increased popularity and fast expansion of the Internet as well as Internet of things, networks are growing rapidly in every corner of the society. As a result, huge amount of data is travelling across the computer networks that lead to the vulnerability of data integrity, confidentiality and reliability. So, network security is a burning issue to keep the integrity of systems and data. The traditional security guards such as firewalls with access control lists are not anymore enough to secure systems. To address the drawbacks of traditional Intrusion Detection Systems (IDSs), artificial intelligence and machine learning based models open up new opportunity to classify abnormal traffic as anomaly with a self-learning capability. Many supervised learning models have been adopted to detect anomaly from networks traffic. In quest to select a good learning model in terms of precision, recall, area under receiver operating curve, accuracy, F-score and model built time, this paper illustrates the performance comparison between Naïve Bayes, Multilayer Perceptron, J48, Naïve Bayes Tree, and Random Forest classification models. These models are trained and tested on three subsets of features derived from the original benchmark network intrusion detection dataset, NSL-KDD. The three subsets are derived by applying different attributes evaluator’s algorithms. The simulation is carried out by using the WEKA data mining tool.

  • 93.
    Abel, Frank
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Kuyumcu, Halit Z.
    TU Berlin.
    Einfluss verschiedener Parameter auf die Verdichtbarkeit und Festigkeit gestampfter Kohlekuchen2008Conference paper (Other academic)
  • 94.
    Abel, Frank
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Kuyumcu, Halit Z.
    Stamped coal cakes in cokemaking technology Part 1 - A parameter study on stampability2009In: Ironmaking & steelmaking, ISSN 0301-9233, E-ISSN 1743-2812, Vol. 36, no 5, p. 321-326Article in journal (Refereed)
  • 95.
    Abel, Frank
    et al.
    TU Berlin.
    Rosenkranz, Jan
    Kuyumcu, Halit Z.
    TU Berlin.
    Stamped coal cakes in cokemaking technology Part 2 - The investigation of cake strength2009In: Ironmaking & steelmaking, ISSN 0301-9233, E-ISSN 1743-2812, Vol. 36, no 5, p. 327-332Article in journal (Refereed)
  • 96.
    Abel, Martin
    et al.
    University of Texas, Physics Department.
    Frommhold, Lothar
    University of Texas, Physics Department.
    Gustafsson, Magnus
    Department of Chemistry, University of Gothenburg.
    Collision-induced absorption at wavelengths near 5 μm by dense hydrogen gas2009In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 131, no 18, article id 181102Article in journal (Refereed)
    Abstract [en]

    Based on a recent ab initiointeraction-induced dipole surface of collisionally interacting molecular hydrogen pairs H2–H2, we compute the binary absorption coefficients at wavelengths near 5 μm at temperatures of 77.5 and 297 K for comparison with existing laboratory measurements. We observe satisfactory agreement of the measurements with our calculations, thereby concluding an earlier study [Gustafsson et al., J. Chem. Phys.119, 12264 (2003)], which was based on an ab initiointeraction-induced dipole surface that was inadequate for the 5 μm band.

  • 97.
    Abel, Martin
    et al.
    University of Texas, Physics Department.
    Frommhold, Lothar
    University of Texas, Physics Department.
    Wang, Fei
    Physics Department, Beijing Institute of Technology, China, University of Texas, Physics Department.
    Gustafsson, Magnus
    Department of Chemistry, University of Gothenburg.
    Li, Xiaoping
    Department of Chemistry, Michigan State University.
    Hunt, Katherine L.C.
    Department of Chemistry, Michigan State University, East Lansing, Department of Chemistry, Michigan State University.
    Collision-induced absorption by supermolecular complexes from a new potential energy and induced dipole surface, suited for calculations up to thousands of kelvin2010In: 20th International Conference on Spectral Line Shapes: St. John's, Newfoundland, Canada, 6 - 11 June 2010 ; [20th ICSLS] / [ed] John K.C. Lewis; Adriana Predoi-Cross, Melville, NY: American Institute of Physics (AIP), 2010, p. 251-257Conference paper (Refereed)
    Abstract [en]

    Absorption by pairs of H2 molecules is an important opacity source in the atmospheres of the outer planets, and thus of special astronomical interest. The emission spectra of cool white dwarf stars differ significantly from the expected blackbody spectra, amongst other reasons due to absorption by H2-H2, H2-He, and H2-H collisional complexes in the stellar atmospheres. To model the radiative processes in these atmospheres, which have temperatures of several thousand kelvin, one needs accurate knowledge of the induced dipole (ID) and potential energy surfaces (PES) of such collisional complexes. These come from quantum-chemical calculations with the H2 bonds stretched or compressed far from equilibrium. Laboratory measurements of collision-induced (CI) absorption exist only at much lower temperature. For H2 pairs at room temperature, the calculated spectra of the rototranslational band, the fundamental band, and the first overtone match the experimental data very well. In addition, with the newly obtained IDS it became possible to reproduce the measurements in the far blue wing of the rototranslational spectrum of H2 at 77.5 K, as well as at 300 K. Similarly good agreement between theory and measurement is seen in the fundamental band of molecular deuterium at room temperature. Furthermore, we also show the calculated absorption spectra of H2-He at 600 K and of H2-H2 at 2,000 K, for which there are no experimental data for comparison

  • 98. Abeysekera, Hemal
    et al.
    Jonsson, Christina
    Problemlösning i två olika länder: en studie om hur elever lyckas lösa problem i den svenska skolan och i den Nya Zeeländska skolan2001Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 99.
    Abeysekera, John
    Luleå tekniska universitet.
    Diversified design needs of personal protective devices and clothing in cold climate: an example in the design needs of protective outdoor winter shoes2000In: Ergonomics of protective clothing: proceedings of NOKOBETEF 6 and 1st European conference on protective clothing held in Stockholm,Sweden, May 7-10, 2000 / [ed] Kalev Kuklane; Ingvar Holmér, Stockholm: Arbetslivsinstitutet , 2000, p. 62-66Conference paper (Refereed)
  • 100.
    Abeysekera, John
    Luleå tekniska universitet.
    Ergonomic problems outside work establishments in industrially developing countries: an example from Sri Lanka1997In: From experience to innovation: proceedings of the 13th triennial congress of the International Ergonomics Association, June 29 - July 4, 1997, Tampere, Finland / [ed] Pentt Seppälä, Taylor and Francis Group , 1997, p. 63-65Conference paper (Refereed)
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