Ändra sökning
Avgränsa sökresultatet
1234567 1 - 50 av 52363
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Disputationsdatum (tidigaste först)
  • Disputationsdatum (senaste först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    A. Oliveira, Roger
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    S. Salles, Rafael
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Rönnberg, Sarah K.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Deep Learning for Power Quality with Special Reference to Unsupervised Learning2023Ingår i: 27th International Conference on Electricity Distribution (CIRED 2023), IEEE, 2023, s. 935-939, artikel-id 10417Konferensbidrag (Refereegranskat)
  • 2.
    A., Trubetskaya
    et al.
    National University of Ireland Galway.
    G. R., Surup
    University of Agder.
    Forsberg, Fredrik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    T., Attard
    University of York.
    A., Hunt
    Khon Kaen University.
    V., Budarin
    University of York.
    V., Abdelsayed
    National Energy Technology Laboratory.
    D., Shekhawat
    National Energy Technology Laboratory.
    The Effect of Wood Composition and Supercritical CO2 Extraction on the Charcoal Production2019Ingår i: 2019 AIChE Annual Meeting proceedings, American Institute of Chemical Engineers, 2019, artikel-id 552cKonferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    This work demonstrated that the coupling of supercritical carbon dioxide extraction with slow pyrolysis is effective to remove over half of extractives from low quality wood and to generate biochar from remaining solid wood fractions. The high yields of extractives from supercritical carbon dioxide extraction illustrates the potential utilizing of low quality wood as an alternative feedstock for the sustainable production of value-added chemicals. Results showed that supercritical carbon dioxide extraction has neither a strong impact on the physical properties of original wood nor on the yield of solid biochar. These results are promising as they show that the biochar obtained for this renewable feedstock could be used as an alternative to fossil-based coke in applications including ferroalloy industries. Moreover, the heat treatment temperature and supercritical carbon dioxide extraction had a significant impact on the tar yields, leading to the increase in naphthalene, polycyclic aromatic hydrocarbons, aromatic and phenolic fractions with the greater temperature. The differences in gasification reactivity and dielectric properties of solid biochars, composition and yields of liquid products of non-treated pinewood and extracted wood fraction emphasize the impact of supercritical carbon dioxide extraction on the pyrolysis process. 

  • 3.
    Aakjær, Mia
    et al.
    Department of Drug Design and Pharmacology, Pharmacovigilance Research Center, University of Copenhagen, Copenhagen, Denmark.
    De Bruin, Marie Louise
    Department of Pharmacy, Copenhagen Centre for Regulatory Science (CORS), University of Copenhagen, Copenhagen, Denmark; Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Utrecht, The Netherlands.
    Kulahci, Murat
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Industriell ekonomi. Department of Applied Mathematics and Computer Science, Technical University of Denmark, Lyngby, Denmark.
    Andersen, Morten
    Department of Drug Design and Pharmacology, Pharmacovigilance Research Center, University of Copenhagen, Copenhagen, Denmark.
    Surveillance of Antidepressant Safety (SADS): Active Signal Detection of Serious Medical Events Following SSRI and SNRI Initiation Using Big Healthcare Data2021Ingår i: Drug Safety, ISSN 0114-5916, E-ISSN 1179-1942, Vol. 44, s. 1215-1230Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Introduction The current process for generating evidence in pharmacovigilance has several limitations, which often lead to delays in the evaluation of drug-associated risks.

    Objectives In this study, we proposed and tested a near real-time epidemiological surveillance system using sequential, cumulative analyses focusing on the detection and preliminary risk quantification of potential safety signals following initiation of selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs).

    Methods We emulated an active surveillance system in an historical setting by conducting repeated annual cohort studies using nationwide Danish healthcare data (1996–2016). Outcomes were selected from the European Medicines Agency's Designated Medical Event list, summaries of product characteristics, and the literature. We followed patients for a maximum of 6 months from treatment initiation to the event of interest or censoring. We performed Cox regression analyses adjusted for standard sets of covariates. Potential safety signals were visualized using heat maps and cumulative hazard ratio (HR) plots over time.

    Results In the total study population, 969,667 new users were included and followed for 461,506 person-years. We detected potential safety signals with incidence rates as low as 0.9 per 10,000 person-years. Having eight different exposure drugs and 51 medical events, we identified 31 unique combinations of potential safety signals with a positive association to the event of interest in the exposed group. We proposed that these signals were designated for further evaluation once they appeared in a prospective setting. In total, 21 (67.7%) of these were not present in the current summaries of product characteristics.

    Conclusion The study demonstrated the feasibility of performing epidemiological surveillance using sequential, cumulative analyses. Larger populations are needed to evaluate rare events and infrequently used antidepressants.

  • 4.
    Aalipour, Mojgan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Human Factors Approach for Maintenance Improvement2015Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    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

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 5.
    Aalipour, Mojgan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    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 study2016Ingår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 7, nr 2, s. 229-238Artikel i tidskrift (Refereegranskat)
    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

  • 6.
    Aalipour, Mojgan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Barabadi, Abbas
    Tromsø University, University of Tromsø - The Arctic University of Norway.
    Work place factors effect on maintainability in challenging operating conditions2015Ingår i: 2015 IEEE International Conference on Industrial Engineering and Engineering Management (IEEM): Singapore, 6-9 Dec. 2015, Piscataway, NJ: IEEE Communications Society, 2015, s. 767-771, artikel-id 7385751Konferensbidrag (Refereegranskat)
    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.

  • 7.
    Aalipour, Mojgan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Singh, Sarbjeet
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Identification of Factors affecting Human performance in Mining Maintenance tasks2014Ingår i: 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, s. 71-76Konferensbidrag (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 8.
    Aaltonen, Harri
    et al.
    Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland.
    Sierla, Seppo
    Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland.
    Kyrki, Ville
    Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland.
    Pourakbari-Kasmaei, Mahdi
    Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland.
    Vyatkin, Valeriy
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap. Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland.
    Bidding a Battery on Electricity Markets and Minimizing Battery Aging Costs: A Reinforcement Learning Approach2022Ingår i: Energies, E-ISSN 1996-1073, Vol. 15, nr 14, artikel-id 4960Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Battery storage is emerging as a key component of intelligent green electricitiy systems. The battery is monetized through market participation, which usually involves bidding. Bidding is a multi‐objective optimization problem, involving targets such as maximizing market compensation and minimizing penalties for failing to provide the service and costs for battery aging. In this article, battery participation is investigated on primary frequency reserve markets. Reinforcement learning is applied for the optimization. In previous research, only simplified formulations of battery aging have been used in the reinforcement learning formulation, so it is unclear how the optimizer would perform with a real battery. In this article, a physics‐based battery aging model is used to assess the aging. The contribution of this article is a methodology involving a realistic battery simulation to assess the performance of the trained RL agent with respect to battery aging in order to inform the selection of the weighting of the aging term in the RL reward formula. The RL agent performs day-ahead bidding on the Finnish Frequency Containment Reserves for Normal Operation market, with the objective of maximizing market compensation, minimizing market penalties and minimizing aging costs.

  • 9.
    Aaltonen, Harri
    et al.
    Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland.
    Sierla, Seppo
    Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland.
    Subramanya, Rakshith
    Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland.
    Vyatkin, Valeriy
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap. Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland; International Research Laboratory of Computer Technologies, ITMO University, 197101 St. Petersburg, Russia.
    A simulation environment for training a reinforcement learning agent trading a battery storage2021Ingår i: Energies, E-ISSN 1996-1073, Vol. 14, nr 17, artikel-id 5587Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Battery storages are an essential element of the emerging smart grid. Compared to other distributed intelligent energy resources, batteries have the advantage of being able to rapidly react to events such as renewable generation fluctuations or grid disturbances. There is a lack of research on ways to profitably exploit this ability. Any solution needs to consider rapid electrical phenomena as well as the much slower dynamics of relevant electricity markets. Reinforcement learning is a branch of artificial intelligence that has shown promise in optimizing complex problems involving uncertainty. This article applies reinforcement learning to the problem of trading batteries. The problem involves two timescales, both of which are important for profitability. Firstly, trading the battery capacity must occur on the timescale of the chosen electricity markets. Secondly, the real-time operation of the battery must ensure that no financial penalties are incurred from failing to meet the technical specification. The trading-related decisions must be done under uncertainties, such as unknown future market prices and unpredictable power grid disturbances. In this article, a simulation model of a battery system is proposed as the environment to train a reinforcement learning agent to make such decisions. The system is demonstrated with an application of the battery to Finnish primary frequency reserve markets.

  • 10.
    Aamir, Muhammad Haseeb
    et al.
    Ecole Nationale Supérieure de Géologie, GeoRessources, University of Lorraine, Vandoeuvre-lès-Nancy, France; University of Engineering and Technology, Lahore, Punjab, Pakistan.
    Gonçalves, Pedro Pereira
    Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Peñalolén, Santiago, Chile.
    Otsuki, Akira
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik. Ecole Nationale Supérieure de Géologie, GeoRessources, University of Lorraine, Vandoeuvre-lès-Nancy, France; Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Peñalolén, Santiago, Chile; Neutron Beam Technology Team, RIKEN Center for Advanced Photonics, RIKEN, Wako, Saitama, Japan.
    Complementary results of non-destructive elemental assay and liberation analysis of waste printed circuit boards2024Ingår i: Non-Destructive Material Characterization Methods / [ed] Otsuki, Akira; Jose, Seiko; Mohan, Manasa; Thomas, Sabu, Elsevier , 2024, s. 767-782Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 11.
    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 problem1987Ingår i: Engineering Costs and Production Economics, ISSN 0167-188X, E-ISSN 1878-4011, Vol. 12, nr 1-4, s. 39-49Artikel i tidskrift (Refereegranskat)
    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.

  • 12.
    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 programs1990Ingår i: European Journal of Operational Research, ISSN 0377-2217, E-ISSN 1872-6860, Vol. 46, nr 3, s. 393-398Artikel i tidskrift (Refereegranskat)
    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

  • 13.
    Aarflot, Markus
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle.
    Jangstam, Pontus
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle.
    Future Logistical Services from Connected Vehicles: A Case Study at Scania CV AB2017Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The road based transportation operations are growing rapidly, but the current infrastructure cannot sustain the entire growth. At the same time vehicle utilisation and fill rates are low. Improved efficiency of the operations is a necessary way forward for road based transportation. Parallel to this, heavy vehicle producers are currently improving the efficiency with services accompanying the product that are focused on the driver and the vehicle performance. However, the data from connected vehicles required for these services only entail a small amount of the operational data generated by connected vehicles. The case study aims to answer how to use connected vehicle operational data in order to suggest value adding services in a dynamic road distribution system. The applied methodology is an inductive study with an explanatory approach to map the current and future service offerings of the case company. This knowledge is combined with an exploratory approach with interviews of transport planners and theories of Lean and fleet management. Primarily, it is concluded that the perspective of operational data requires widening. Considering not only driver and vehicle operations but rather the entire transport operation of a company. It is also concluded that value creation with operational data is possible during three phases of fleet management. First, if knowledge about order data is accessible, the planning of transportations can be improved using route optimisation and operations research. Secondly, it is possible to create value during the execution phase, throughless manual supervision and communication by transport planners. Lastly, both the currently used operational data and further data usage can contribute to a better understanding of the performance of a fleet operation and facilitate for continuous improvements during an evaluation phase.

    Ladda ner fulltext (pdf)
    fulltext
  • 14.
    Aarnio, Laura
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik.
    Att utveckla digital kompetens hos de yngsta barnen: Ett förskollärarperspektiv på arbetet med 1- och 2-åringar2023Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Denna studie tar sin grund i det sociokulturella perspektivet och fokuserar på digital kompetens hos de yngsta barnen utifrån ett förskollärarperspektiv. Det ansågs som intressant att ta reda på hur förskolan arbetar med digitalisering med 1- och 2-åringar på ett sätt som lägger grunden för det livslånga lärandet och ger förutsättningar för individen som en aktiv deltagare i det digitala samhället. För att kunna svara på studiens syfte och frågeställningar föll valet på att intervjua verksamma förskollärare som arbetar på avdelningar för yngre barn. 

    Tillgång till digitala verktyg och utforskande både självständigt och tillsammans med andra framhävs i denna studie som centralt. Förskollärare har lite olika perspektiv på arbetssätt och på vad som är viktigt för de yngsta barnen att lära sig när det gäller digital teknik och kompetens. Förskollärarens eget engagemang och kompetens påverkar hur undervisningen ser ut. Det är viktigt att kunna balansera mellan att ge barnen möjligheter att utforska tillsammans och självständigt samtidigt som läraren finns tillgänglig och närvarande för att vid behov kunna erbjuda stöd samt ta vara på lärandetillfällen. En närvarande och kompetent pedagog har möjligheten att få mycket information kring barnens digitala kompetens samt dem intressen de har. De flesta verksamheterna hade ingen tydlig planering eller strategi för digitalisering utan digital teknik blev ett ständigt närvarande redskap som används kontinuerligt och kompletterar andra områden inom undervisning och lek. Digitala verktyg utvidgar lärmiljön och skapar nya rumsliga dimensioner.

    Ladda ner fulltext (pdf)
    fulltext
  • 15.
    Aarrevaara, Timo
    et al.
    Helsingfors Universitet.
    Berg, Elisabeth
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Arbetsvetenskap.
    Higher Education and Research: Who should pay?2014Rapport (Refereegranskat)
    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 16.
    Aarrevaara, Timo
    et al.
    Helsingfors Universitet.
    Berg, Elisabeth
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Arbetsvetenskap.
    Introduction2014Ingår i: Higher Education and Research in Academe: Who should pay?, Luleå: Luleå tekniska universitet, 2014, s. 11-17Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Ladda ner fulltext (pdf)
    FULLTEXT01
  • 17.
    Aaröe, Olivia
    et al.
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik.
    Ullenius Ekengren, Fanny
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik.
    Personers upplevelser av att leva med lungfibros: En litteraturstudie2023Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Bakgrund: Lungfibros är en kronisk respiratorisk sjukdom som kännetecknas av nedsatt lungfunktion och andningssvårigheter. Det finns otillräckliga resurser i form av stöd för personen som drabbats av lungfibros och sjukdomen missförstås av hälso-och sjukvårdspersonal och samhället. Behandlingen är bristfällig och fokuserar i dagsläget på att förebygga, behandla och lindra symtom för att öka livskvaliteten för personen som är drabbad. Det finns utmaningar med vård som enbart fokuserar på symtomlindring och det finns behov av ytterligare insatser för att uppnå en förbättrad livskvalitet hos den enskilda personen med lungfibros. Syfte: Att beskriva personers upplevelser av att leva med lungfibros. Metod: Litteraturstudie med induktiv ansats där tio vetenskapliga artiklar har analyserats med kvalitativ manifest innehållsanalys. Resultat: Analysen resulterade i fem slutkategorier som beskriver personers upplevelser av att leva med lungfibros: en turbulent resa från symtom till diagnos, att känna en inre och yttre påverkan, en förändring och påverkan i det dagliga livet, att ha behov av stöd och information, och att ha funderingar inför en oviss framtid. Slutsats: För personer som lever med lungfibros och deras närstående är stöd, information och copingstrategier avgörande i det dagliga livet. Sjuksköterskan har en viktig roll gällande kommunikation och den bör vara personcentrerad och anpassad till personens behov och takt. Samtal om livets slutskede är nödvändigt för personer med lungfibros, men brister ofta i vård och omvårdnad av denna patientgrupp. 

    Ladda ner fulltext (pdf)
    fulltext
  • 18.
    Aas, Gro Hanne
    Luleå tekniska universitet.
    Kvinneforskningspolitiske (pr)øvelser1999Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    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.

  • 19.
    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 tekniska universitet, Institutionen för hälsovetenskap, Hälsa och rehabilitering.
    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 Trial2015Ingår i: Journal of Orthopaedic and Sports Physical Therapy, ISSN 0190-6011, E-ISSN 1938-1344, Vol. 45, nr 2, s. 77-85Artikel i tidskrift (Refereegranskat)
    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).

  • 20.
    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 tekniska universitet, Institutionen för hälsovetenskap, Hälsa och rehabilitering.
    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 pain2011Ingår i: Physiotherapy, ISSN 0031-9406, E-ISSN 1873-1465, Vol. 97, nr Suppl. 1, s. eS18-Artikel i tidskrift (Refereegranskat)
    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.

  • 21.
    Aasa, Björn
    et al.
    Department of Orthopaedics, Surgical and Perioperative Sciences, Umeå University, Norrlandsklinikens hälsocentral, Umeå.
    Sandlund, Jonas
    Michaelson, Peter
    Luleå tekniska universitet, Institutionen för hälsovetenskap, Hälsa och rehabilitering.
    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 pain2012Ingår i: Rendez vous of hands and minds: 10th International Federation of Orthopaedic Manipulative Physical Therapists’ World conference, Quebec,  1-5 Oct 2012, 2012, nr 2Konferensbidrag (Refereegranskat)
  • 22.
    Aasa, Johan
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Linear-Quadratic Regulation of ComputerRoom Air Conditioners2018Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Data centers operations are notoriously energy-hungry, with the computing and cooling infrastructures drawing comparable amount of electrical power to operate. A direction to improve their efciency is to optimizethe cooling, in the sense of implementing cooling infrastructures controlschemes that avoid performing over-cooling of the servers.Towards this direction, this work investigates minimum cost linearquadratic control strategies for the problem of managing air cooled datacenters. We derive a physical and a black box model for a general datacenter, identify this model from real data, and then derive, present andtest in the eld a model based Linear-Quadratic Regulator (LQR) strategy that sets the optimal coolant temperature for each individual coolingunit. To validate the approach we compare the eld tests from the LQR strategy against classical Proportional-Integral-Derivative (PID) controlstrategies, and show through our experiments that it is possible to reducethe energy consumption with respect to the existing practices by severalpoints percent without harming the servers within the data center fromthermal perspectives.

    Ladda ner fulltext (pdf)
    fulltext
  • 23.
    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 tekniska universitet, Institutionen för hälsovetenskap, Hälsa och rehabilitering.
    Sandlund, Jonas
    Effects of low- and high-load motor control exercises on lumbar curvature during stance in patients with low back pain2012Ingår i: Rendez vous of hands and minds: 10th International Federation of Orthopaedic Manipulative Physical Therapists’ World conference, Quebec,  1-5 Oct 2012, 2012, nr 2Konferensbidrag (Refereegranskat)
  • 24.
    Aaskoven, Mette
    et al.
    Luleå tekniska universitet, Institutionen för hälsovetenskap, Omvårdnad.
    Hietala, Ulrika
    Luleå tekniska universitet, Institutionen för hälsovetenskap, Omvårdnad.
    Föräldrars upplevelse av att ha ett barn med diabetes typ 12019Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Bakgrund: Typ 1 diabetes är en sjukdom som mer än 500 000 barn och unga under 17 år lever med och kräver livslång behandling. För barnens föräldrar innebär detta en omställning i det dagliga livet och i deras föräldraskap. Föräldrarna kan ha behov av stöttning från vårdpersonal. Syfte: Att beskriva föräldrars upplevelse av att ha ett barn med typ 1 diabetes. Metod: Kvalitativ manifest innehållsanalys användes som analysmetod och 12 vetenskapliga artiklar med kvalitativ ansats ingick i resultatet. Analysen resulterade i fem slutgiltiga kategorier. Resultat: Föräldrar till ett barn med typ 1 diabetes kan uppleva att diagnosen förändrar livet. Vardagen styrs av kontroll och planering vilket leder till många känslor som är svåra att hantera. Föräldrarna behöver tillgänglighet från vårdpersonal och andra för att känna trygghet och för att kunna hantera livet med ett barn med diabetes typ 1. Slutsatser: För att sjuksköterskan ska kunna ge en god omvårdnad är det av betydelse att hen kan relatera till både patienter och anhöriga. Sjukvården har en viktig roll att genom stor tillgänglighet och uppbackning vara ett stöd och därmed vara en trygghet för familjerna i vardagen. Denna studies resultat kan ge en ökad förståelse för föräldrars upplevelse av att ha barn med diabetes typ 1. Det behövs mer kunskap inom området för att sjuksköterskor ska kunna bemöta och stötta familjerna vilket kan leda till förbättrad omvårdnad.

    Ladda ner fulltext (pdf)
    fulltext
  • 25.
    Aava, Nils
    et al.
    Luleå tekniska universitet.
    Ericson, Ronald
    Luleå tekniska universitet.
    Esberg, Lars
    Luleå tekniska universitet.
    Belysning i bilverkstäder: förslag till belysningsplanering1979Rapport (Övrigt vetenskapligt)
  • 26.
    Abadei, S.
    et al.
    Department of Microelectronics, Chalmers University of Technology, Gothenburg, Sweden.
    Gevorgian, S
    Department of Microelectronics, Chalmers University of Technology, Gothenburg, Sweden;Core Unit Research Center, Ericsson Microwave Systems, Mölndal, Sweden.
    Cho, C.-R
    Department of Condensed Matter Physics, Royal Institute of Technology, Stockholm, Sweden.
    Grishin, A.
    Department of Condensed Matter Physics, Royal Institute of Technology, Stockholm, Sweden.
    Andreasson, Johanna
    Luleå tekniska universitet.
    Lindbäck, Ture
    Luleå tekniska universitet.
    DC field dependent properties of Na0.5 K0.5 NbO3/SiO2/Si structures at millimeter-wave frequencies2001Ingår i: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 78, nr 13, s. 1900-1902Artikel i tidskrift (Refereegranskat)
    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

  • 27.
    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 tekniska universitet, Institutionen för teknikvetenskap och matematik.
    Microwave properties of tunable capacitors basee on magnetron sputtered ferroelectric Na0.5K0.5NbO3 film on low and high resistivity silicon substrates2001Ingår i: Integrated Ferroelectrics, ISSN 1058-4587, E-ISSN 1607-8489, Vol. 39, nr 1-4, s. 359-366Artikel i tidskrift (Refereegranskat)
    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

  • 28.
    Aban, Saman
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle.
    Principalansvaret för vårdnadshavare: Föräldrars skadeståndsansvar för skada vållad av barn2016Självständigt arbete på grundnivå (kandidatexamen), 180 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Personer under 15 år kan inte straffrättsligt bli ansvariga för brott de begått i enlighet med 1 kap 6§ BrB. Däremot kan en civilrättslig process gällande skadeståndsrättsligt anspråk bli aktuell i princip oberoende av skadevållarens ålder. Huvudregeln är alltså att barn kan bli skadeståndsskyldiga på samma sätt som en vuxen om de anses ha vållat skada. De större utmärkande skillnaderna mellan att hålla ett barn jämfört med en vuxen skadeståndsskyldig är att det görs en så kallad skälighetsbedömning när det gäller barn och även vid bedömning av barns culpa tar man mindre hänsyn till de subjektiva kriterierna. I denna uppsats utreds vårdnadshavarens ansvar enligt 3 kap. 5§ skadeståndslagen som infördes år 2010. Denna reglering innebär att föräldrar kan blir skadeståndsansvariga för skador som deras barn orsakar genom brott samt genom tillsynsansvaret som regleras i 6 kap. 2§ föräldrabalken. Denna paragraf reglerar att vårdnadshavaren skall ge barnet den tillsyn och uppsikt det behöver medhänsyn till ålder, utveckling och övriga omständigheter för att hindra skadevållande handlingar. Skillnaden mellan dessa respektive lagregler gällande att vårdnadshavaren skall anses vara skadeståndsansvarig är att den förra förutsätter att barnet begått ett brott och förutsätter heller ej culpa medan den senare inte gör det.

    Ladda ner fulltext (pdf)
    fulltext
  • 29.
    Abaray, Lahcen
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik.
    Development and Characterization Of Ceramic Particles Reinforced Metal Matrix Composites2023Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Wear is a significant challenge encountered in the mining industry, affecting the durability and performance of materials. Hadfield steel has emerged as a commonly used material in this field due to its favorable properties. However, there is a persistent need to enhance its service life. Metal matrix composites (MMCs) offer a potential solution to address this issue. By reinforcingHadfield steel with ceramic particles, MMCs aim to improve the material's wear resistance and extend its operational lifespan. This study specifically investigates the potential of MMCs, reinforced with Zirconia Toughened Alumina (ZTA) particles, to enhance the performance of Hadfield steel in mining applications. Notably, ZTA particles are chosen for their exceptional wear resistance and low cost, making them an attractive reinforcement option. The mechanical behavior and properties of ZTA particle reinforced metal matrix composites (MMCs) were thoroughly investigated by conducting a comprehensive analysis. This analysis encompassed adetailed examination of the microstructure, composition, distribution, as well as the bonding between ZTA particles and the metallic matrix, along with rigorous measurements of hardness and wear resistance. The findings of the study reveal that the ZTA particle reinforced MMCs exhibit a uniform dispersion of ZTA particles throughout the composite material. This homogeneous distribution contributes to notable enhancements in the average hardness of the MMCs, surpassing that of Hadfield steel alone. However, the study did not observe a substantial enhancement in the wear resistance of the material.

  • 30.
    Abarkan, Abdellah
    et al.
    Blekinge tekniska högskola, Karlskrona, Sverige.
    Rizzo, Agatino
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Öjehag-Pettersson, Andreas
    Karlstads universitet, Karlstad, Sverige.
    Byerley, Andrew
    Stockholms universitet, Stockholm, Sverige.
    Karvonen, Andy
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Legby, Ann
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Braide, Anna
    Chalmers tekniska högskola, Göteborg, Sverige.
    Hellström, Björn
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Christophers, Brett
    Uppsala Universitet, Uppsala, Sverige.
    Johansson, Britt-Marie
    Lunds universitet, Lund, Sverige.
    Yigit Turan, Burcu
    Sveriges lantbruksuniversitet, Uppsala, Sverige.
    Listerborn, Carina
    Malmö universitet, Malmö, Sverige.
    Dyrssen, Catharina
    Chalmers tekniska högskola, Göteborg, Sverige.
    Gabrielsson, Catharina
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Thörn, Catharina
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Mukhtar-Landgren, Dalia
    Lunds universitet, Lund, Sverige.
    Koch, Daniel
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Polanska, Dominika V
    Uppsala universitet, Uppsala, Sverige.
    Högström, Ebba
    Blekinge tekniska högskola, Karlskrona, Sverige.
    Nilsson, Emma
    Lunds universitet, Lund, Sverige.
    Clark, Eric
    Lunds universitet, Lund, Sverige.
    Stenberg, Erik
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Andersson, Eva
    Stockholms universitet, Stockholm, Sverige.
    Berggård, Glenn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Henriksson, Greger
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Lindholm, Gunilla
    Sveriges lantbruksuniversitet, Uppsala, Sverige.
    Sandin, Gunnar
    Lunds universitet, Lund, Sverige.
    Forsberg, Gunnel
    Stockholms universitet, Stockholm, Sverige.
    Baeten, Guy
    Malmö universitet, Malmö, Sverige.
    Cars, Göran
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Rohracher, Harald
    Linköpings universitet, Linköping, Sverige.
    Westlund, Hans
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Mattsson, Helena
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Frichot, Hélène
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Palmer, Henrietta
    Chalmers tekniska högskola, Göteborg, Sverige.
    Corvellec, Hervé
    Lunds universitet, Lund, Sverige.
    Thörn, Håkan
    Göteborgs universitet, Göteborg, Sverige.
    Sandström, Ida
    Lunds universitet, Lund, Sverige.
    Lindell, Ilda
    Stockholms universitet, Stockholm, Sverige.
    Werner, Inga Britt
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Molina, Irene
    Uppsala universitet, Uppsala, Sverige.
    Mack, Jennifer
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Stenberg, Jenny
    Chalmers tekniska högskola, Göteborg, Sverige.
    Magnusson, Jesper
    Lunds universitet, Lund, Sweden.
    Metzger, Jonathan
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Wangel, Josefin
    Sveriges lantbruksuniversitet, Uppsala, Sverige.
    Fredriksson, Julia
    Chalmers tekniska högskola, Göteborg, Sverige.
    Bradley, Karin
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Grundström, Karin
    Malmö universitet, Malmö, Sverige.
    Nylund, Katarina
    Malmö universitet, Malmö, Sverige.
    Grange, Kristina
    Chalmers tekniska högskola, Göteborg, Sverige.
    Nilsson, Kristina L.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Ståhl, Lars-Henrik
    Lunds universitet, Lund, Sverige.
    Olsson, Lina
    Malmö universitet, Malmö, Sverige.
    Soneryd, Linda
    Göteborgs universitet, Göteborg, Sverige.
    Smas, Lukas
    Stockholms universitet, Stockholm, Sverige.
    Hellström Reimer, Maria
    Malmö universitet, Malmö, Sverige.
    Håkansson, Maria
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Zapata Campos, María José
    Göteborgs universitet, Göteborg, Sverige.
    Franzén, Mats
    Uppsala universitet, Uppsala, Sverige.
    Kärrholm, Mattias
    Lunds universitet, Lund, Sverige.
    Qviström, Mattias
    Sveriges lantbruksuniversitet, Uppsala, Sverige.
    Schalk, Meike
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Tesfahuney, Mekonnen
    Karlstads universitet, Karlstad, Sverige.
    Tahvilzadeh, Nazem
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Björling, Nils
    Chalmers tekniska högskola, Göteborg, Sverige.
    Nylander, Ola
    Chalmers tekniska högskola, Göteborg, Sverige.
    Zapata, Patrik
    Göteborgs universitet, Göteborg, Sverige.
    Femenías, Paula
    Chalmers tekniska högskola, Göteborg, Sverige.
    Hagbert, Pernilla
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Schmitt, Peter
    Stockholms universitet, Stockholm, Sverige.
    Ek, Richard
    Lunds universitet, Lund, Sverige.
    Andersson, Roger
    Uppsala universitet, Uppsala, Sverige.
    Johansson, Rolf
    Sveriges lantbruksuniversitet, Uppsala, Sverige.
    Kopljar, Sandra
    Lunds universitet, Lund, Sverige.
    Borgström, Sara
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Brorström, Sara
    Göteborgs universitet, Göteborg, Sverige.
    Schmidt, Staffan
    Malmö universitet, Malmö, Sverige.
    Gromark, Sten
    Chalmers tekniska högskola, Göteborg, Sverige.
    Westerdahl, Stig
    Malmö universitet, Malmö, Sverige.
    Holgersen, Ståle
    Uppsala Universitet, Uppsala, Sverige.
    Urban, Susanne
    Uppsala Universitet, Uppsala, Sverige.
    Salonen, Tapio
    Malmö universitet, Malmö, Sverige.
    Borén, Thomas
    Stockholms universitet, Stockholm, Sverige.
    Haas, Tigran
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Glad, Wiktoria
    Linköpings universitet, Linköping, Sverige.
    Svane, Örjan
    Kungliga tekniska högskolan, Stockholm, Sverige.
    Lyssna på forskningen: Den visar på avregleringens problem2019Ingår i: Dagens nyheter, ISSN 1101-2447, nr 10/21/2019Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Ladda ner fulltext (pdf)
    fulltext
  • 31.
    Abba, Alia Besma
    et al.
    Laboratory of Water and Environment Engineering in Saharan Environment, University of Ouargla, PB 147 RP, Ouargla 30000, Algeria.
    Saggai, Sofiane
    Laboratory of Water and Environment Engineering in Saharan Environment, University of Ouargla, PB 147 RP, Ouargla 30000, Algeria.
    Touil, Youcef
    Laboratory of Biogeochemical of Desert Environment, University of Ouargla, PB 147 RP, Ouargla 30000, Algeria.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Kouadri, Saber
    Laboratory of Water and Environment Engineering in Saharan Environment, University of Ouargla, PB 147 RP, Ouargla 30000, Algeria.
    Nouasria, Fatima Zohra
    Dynamic Interactions and Reactivity of Systems, University of Ouargla, PB 147 RP, Ouargla 30000, Algeria.
    Najm, Hadee Mohammed
    Department of Civil Engineering, Zakir Husain Engineering College, Aligarh Muslim University, Aligarh 202002, India.
    Mashaan, Nuha S.
    Faculty of Science and Engineering, School of Civil and Mechanical Engineering, Curtin University, Bentley, WA 6102, Australia.
    Eldirderi, Moutaz Mustafa A.
    Department of Chemical Engineering, College of Engineering, King Khalid University, Abha 61421, Saudi Arabia.
    Khedher, Khaled Mohamed
    Department of Civil Engineering, College of Engineering, King Khalid University, Abha 61421, Saudi Arabia; Department of Civil Engineering, High Institute of Technological Studies, Mrezgua University Campus, Nabeul 8000, Tunisia.
    Copper and Zinc Removal from Wastewater Using Alum Sludge Recovered from Water Treatment Plant2022Ingår i: Sustainability, E-ISSN 2071-1050, Vol. 14, nr 16, artikel-id 9806Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The study aimed to determine Aluminum sludge composition and structure for its valorisation as an alternative natural material for heavy metals removal from wastewater for further reuse as treated water in different applications. The study was conducted to investigate the introduction of Al-bearing sludge composition. The physical and chemical properties were examined using X-ray diffraction tests (XRD), scanning electron microscope tests (SEM), Fourier-transform infrared tests (FTIR), and Brunauer-Emmett-Teller tests (BET). Furthermore, the heavy metal concentrations of synthetic wastewater were measured using the spectrophotometry method. The experimental procedure is based on testing different pH limits and amounts of aluminum sludge to find the optimum conditions for copper (Cu) and zinc (Zn) removal. The results demonstrated a high removal efficiency where its value reached up to 97.4% and 96.6% for Zn and Cu, respectively, in an acidic medium (pH = 6) using a relatively high amount of sludge (1400 mg). Nevertheless, a low efficiency was obtained in the strongly acidic medium (pH = 4) and a smaller sludge amount of about 480 mg.

  • 32.
    Abba, S. I.
    et al.
    Department of Civil Engineering, Faculty of Engineering, Baze University, Abuja, Nigeria.
    Abdulkadir, R. A.
    Department of Electrical Engineering, Kano University of Science and Technology, Wudil, Nigeria.
    Gaya, M. S.
    Department of Electrical Engineering, Kano University of Science and Technology, Wudil, Nigeria.
    Sammen, Saad Sh.
    Department of Civil Engineering, College of Engineering, University of Diyala, Diyala Governorate, Iraq.
    Ghali, Umar
    Department of Medical Biochemistry, Faculty of Medicine, Near East University, Mersin-10, Nicosia, North Cyprus, 99138, Turkey.
    Nawaila, M. B.
    Department of Computer Science Education, Aminu Saleh College of Education, Azare, Nigeria.
    Oğuz, Gözde
    Department of Electrical and Electronic Engineering, Faculty of Civil and Environmental Engineering, Near East University, Mersin 10, Nicosia, North Cyprus, Turkey.
    Malik, Anurag
    Punjab Agricultural University, Regional Research Station, Bathinda, Punjab, 151001, India.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Effluents quality prediction by using nonlinear dynamic block-oriented models: A system identification approach2021Ingår i: Desalination and Water Treatment, ISSN 1944-3994, E-ISSN 1944-3986, Vol. 218, s. 52-62Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The dynamic and complex municipal wastewater treatment plant (MWWTP) process should be handled efficiently to safeguard the excellent quality of effluents characteristics. Most of the available mathematical models do not efficiently capture the MWWTP process, in such cases, the data-driven models are reliable and indispensable for effective modeling of effluents characteristics. In the present research, two nonlinear system identification (NSI) models namely; Hammerstein-Wiener model (HW) and nonlinear autoregressive with exogenous (NARX) neural network model, and a classical autoregressive (AR) model were proposed to predict the characteristics of the effluent of total suspended solids (TSSeff) and pHeff from Nicosia MWWTP in Cyprus. In order to attain the optimal models, two different combinations of input variables were cast through auto-correla-tion function and partial auto-correlation analysis. The prediction accuracy was evaluated using three statistical indicators the determination coefficient (DC), root mean square error (RMSE) and correlation coefficient (CC). The results of the appraisal indicated that the HW model outperformed NARX and AR models in predicting the pHeff, while the NARX model performed better than the HW and AR models for TSSeff prediction. It was evident that the accuracy of the HW increased averagely up to 18% with regards to the NARX model for pHeff . Likewise, the TSSeff performance increased averagely up to 25% with regards to the HW model. Also, in the validation phase, the HW model yielded DC, RMSE, and CC of 0.7355, 0.1071, and 0.8578 for pHeff, while the NARX model yielded 0.9804, 0.0049 and 0.9902 for TSSeff, respectively. For comparison with the traditional AR, the results showed that both HW and NARX models outperformed in (TSSeff) and pHeff prediction at the study location. Hence, the outcomes determined that the NSI model (i.e., HW and NARX) are reliable and resilient modeling tools that could be adopted for pHeff and TSSeff prediction.

    Ladda ner fulltext (pdf)
    fulltext
  • 33.
    Abba, S.I.
    et al.
    Faculty of Engineering, Department of Civil Engineering, Baze University, Abuja, Nigeria; Interdisciplinary Research Center for Membrane and Water Security, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.
    Abdulkadir, R.A.
    Department of Electrical Engineering, Kano University of Science and Technology, Wudil, Nigeria.
    Sammen, Saad Sh.
    Department of Civil Engineering, College of Engineering, University of Diyala, Diyala Governorate, Iraq.
    Pham, Quoc Bao
    Faculty of Natural Sciences, Institute of Earth Sciences, University of Silesia in Katowice, Będzińska street 60, 41-200, Sosnowiec, Poland.
    Lawan, A.A.
    Department of Computer Science, Kano University of Science and Technology, Wudil, Nigeria.
    Esmaili, Parvaneh
    Department of Electrical and Electronic Engineering Near East University, Nicosia, North Cyprus, Turkey.
    Malik, Anurag
    Punjab Agricultural University, Regional Research Station, Bathinda 151001, Punjab, India.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Integrating feature extraction approaches with hybrid emotional neural networks for water quality index modeling2022Ingår i: Applied Soft Computing, ISSN 1568-4946, E-ISSN 1872-9681, Vol. 114, artikel-id 108036Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The establishment of water quality prediction models is vital for aquatic ecosystems analysis. The traditional methods of water quality index (WQI) analysis are time-consuming and associated with a high degree of errors. These days, the application of artificial intelligence (AI) based models are trending for capturing nonlinear and complex processes. Therefore, the present study was conducted to predict the WQI in the Kinta River, Malaysia by employing the hybrid AI model i.e., GA-EANN (genetic algorithm-emotional artificial neural network). The extreme gradient boosting (XGB) and neuro-sensitivity analysis (NSA) approaches were utilized for feature extraction, and six different model combinations were derived to examine the relationship among the WQI with water quality (WQ) variables. The efficacy of the proposed hybrid GA-EANN model was evaluated against the backpropagation neural network (BPNN) and multilinear regression (MLR) models during calibration, and validation periods based on Nash–Sutcliffeefficiency (NSE), mean square error (MSE), root mean square error (RMSE), mean absolute percentage error (MAPE), and correlation coefficient (CC) indicators. According to results of appraisal the hybrid GA-EANN model produced better outcomes (NSE = 0.9233/ 0.9018, MSE = 10.5195/ 9.7889 mg/L, RMSE = 3.2434/ 3.1287 mg/L, MAPE = 3.8032/ 3.0348 mg/L, CC = 0.9609/ 0.9496) in calibration/ validation phases than BPNN and MLR models. In addition, the results indicate the better performance and suitability of the hybrid GA-EANN model with five input parameters in predicting the WQI for the study site.

    Ladda ner fulltext (pdf)
    fulltext
  • 34.
    Abbas, Ghulam
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Maskinelement.
    Johansson, Gustav
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Alay-e-Abbas, Syed Muhammad
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Computational Materials Modeling Laboratory, Department of Physics, Government College University, Faisalabad 38040, Pakistan.
    Shi, Yijun
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Maskinelement.
    Larsson, J. Andreas
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Quasi Three-Dimensional Tetragonal SiC Polymorphs as Efficient Anodes for Sodium-Ion Batteries2023Ingår i: ACS Applied Energy Materials, E-ISSN 2574-0962, Vol. 6, nr 17, s. 8976-8988Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In the present work, we investigate, for the first time, quasi 3D porous tetragonal silicon–carbon polymorphs t(SiC)12 and t(SiC)20 on the basis of first-principles density functional theory calculations. The structural design of these q3-t(SiC)12 and q3-t(SiC)20 polymorphs follows an intuitive rational approach based on armchair nanotubes of a tetragonal SiC monolayer where C–C and Si–Si bonds are arranged in a paired configuration for retaining a 1:1 ratio of the two elements. Our calculations uncover that q3-t(SiC)12 and q3-t(SiC)20 polymorphs are thermally, dynamically, and mechanically stable with this lattice framework. The results demonstrate that the smaller polymorph q3-t(SiC)12 shows a small band gap (∼0.59 eV), while the larger polymorph of q3-t(SiC)20 displays a Dirac nodal line semimetal. Moreover, the 1D channels are favorable for accommodating Na ions with excellent (>300 mAh g–1) reversible theoretical capacities. Thus confirming potential suitability of the two porous polymorphs with an appropriate average voltage and vanishingly small volume change (<6%) as anodes for Na-ion batteries.

    Ladda ner fulltext (pdf)
    fulltext
  • 35.
    Abbas, Maisaa
    et al.
    Luleå tekniska universitet, Institutionen för hälsovetenskap.
    Andersson, Elisa
    Luleå tekniska universitet, Institutionen för hälsovetenskap.
    Personers upplevelser av att överleva ett hjärtstopp - ett litteraturstudie2019Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Hjärtstopp drabbar cirka 10 000 personer årligen i Sverige. Antalet personer som överlever ett hjärtstopp har ökat stadigt de sista åren, men fortfarande är det den vanligaste orsaken till plötslig död utanför sjukhus. För de personen som överlever innebär det att livet plötsligt förändras och fokus i det dagliga livet blir på händelsen och dess konsekvenser. Syftet med denna litteraturstudie var att beskriva de drabbades upplevelser av ett hjärtstopp. En kvalitativ design användes och nio vetenskapliga studier analyserades systematiskt med innehållsanalys. Analysen resulterade i fem kategorier: Att känna oro, att få ett nytt livsperspektiv, att kroppsliga begränsningar leder till känslor av rädsla och maktlöshet, att känna tacksamhet men vara i behov av stödsamtal, att vara i behov av information. Resultatet visade att personer som överlevt ett hjärtstopp hade många frågor och funderingar kring det inträffade men upplevde att de fick bristande information från sjukvården. Känslor som otrygghet, ångest och osäkerhet var vanligt samt oro inför framtiden. Resultatet från denna litteraturstudie kan användas för att öka kunskapen om hur personerna mår psykiskt och fysiskt, samt vilka behov de har för att hantera livet. Det behövs mer omvårdnadsforskning inom området med fokus på sjuksköterskors upplevelser av att vårda de drabbade personerna. Målet är att skapa trygghet hos sjukvårdspersonal så att de kan stötta dessa personer på bästa sätt och främja en läkning hos dem och anhöriga.

    Ladda ner fulltext (pdf)
    fulltext
  • 36.
    Abbas, Nahla
    et al.
    School of Engineering & Technology, Central Queensland University, Melbourne, Australia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    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 Change2019Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 11, nr 8, s. 437-442Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    fulltext
  • 37.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Climate Change Impacts on Water Resources of Greater Zab River, Iraq2016Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 10, nr 12, s. 1384-1402Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    Climate Change Impacts on Water Resources of Greater
  • 38.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Impacts of Climate Change on Water Resources in Diyala River Basin, Iraq2016Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 10, nr 9, s. 1059-1074Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    fulltext
  • 39.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Model-Based Assessment of Climate Change Impact on Isaac River Catchment, Queensland2016Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, nr 7, s. 460-470Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    fulltext
  • 40.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    The Impacts of Climate Change on Fitzroy River Basin, Queensland, Australia2017Ingår i: Journal of Civil Engineering and Architecture, ISSN 1934-7359, E-ISSN 1934-7367, Vol. 11, nr 1, s. 38-47Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    fulltext
  • 41.
    Abbas, Nahla
    et al.
    School of Engineering & Technology, Central Queensland University, Melbourne, Australia.
    Wasimi, Saleh
    School of Engineering & Technology, Central Queensland University, Melbourne, Australia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sultana, Nasrin
    RMIT University, Melbourne, Australia.
    Water resources problems of Iraq: Climate change adaptation and mitigation2018Ingår i: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 26, artikel-id 6Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    fulltext
  • 42.
    Abbas, Nahlah
    et al.
    Central Queensland University, Melbourne, Australia.
    Nasrin, Sultana
    RMIT, Melbourne, Australia.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ali, Sabah H.
    Remote Sensing Center, University of Mosul, Mosul, Iraq.
    The Impacts of Sea Level Rise on Basrah City,Iraq: The Impacts of Sea Level Rise on Basrah City,Iraq2020Ingår i: Open Journal of Geology, ISSN 2161-7570, E-ISSN 2161-7589, Open Journal of Geology, ISSN 2161-7570, Vol. 10, nr 12, s. 1189-1197Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sea Level Rise (SLR) above the Mean Sea Level (MSL) is more likely to cause a significant risk to the coastal regions. This research explores the potential impact of sea level rise, due to climate change, on coastal areas. It examines the impact of sea level rise on Basrah city and adjacent cities in Iraq. A digital elevation model (DEM) was used to create a model of Potentially Inundated Areas, manipulated and processed in Geographical Information System version 10.7 (ArcGIS 10.7). Through this model, the impact of sea level rise was assessed on the surface area. After the susceptible areas were delineated, it was estimated that at worst case scenario of 5 m sea level rise will impact Basrah city by losing 38 percent of its total surface area.

    Ladda ner fulltext (pdf)
    fulltext
  • 43.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Impacts of Climate Change on Water Resources of Greater Zab and Lesser Zab Basins, Iraq, Using Soil and Water Assessment Tool Model2017Ingår i: International Journal of Environmental, Chemical, Ecological, Geological and Geophysical Engineering, ISSN 2010-376X, Vol. 11, nr 10, s. 823-829Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    fulltext
  • 44.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    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 Measures2018Ingår i: Water, E-ISSN 2073-4441, Vol. 10, nr 11, s. 1-19, artikel-id 1562Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    fulltext
  • 45.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment of Climate Change Impact on Water Resources of Lesser Zab, Kurdistan, Iraq Using SWAT Model2016Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, s. 697-715Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    fulltext
  • 46.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment of Climate Change Impacts on Water Resources of Al-Adhaim, Iraq Using SWAT Model2016Ingår i: Engineering, ISSN 1947-3931, E-ISSN 1947-394X, Vol. 8, s. 716-732Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    fulltext
  • 47.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Assessment of climate change impacts on water resources of Khabour in Kurdistan , Iraq using SWAT model2016Ingår i: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Vol. 24, s. 1-21, artikel-id 10Artikel i tidskrift (Refereegranskat)
    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.

    Ladda ner fulltext (pdf)
    Khabour
  • 48.
    Abbas, Syed Adeel
    et al.
    Center for High Energy Physics, University of the Punjab, Quaid-e-Azam Campus, 54590 Lahore, Pakistan.
    Mahmood, I.
    Center for High Energy Physics, University of the Punjab, Quaid-e-Azam Campus, 54590 Lahore, Pakistan.
    Sajjad, Muhammad
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Noor, N.A.
    Department of Physics, RIPHAH International University, Campus Lahore, Pakistan.
    Mahmood, Q.
    Department of Physics, College of Science, Imam Abdulrahman Bin Faisal University, P O Box 1982, 31441 Dammam, Saudi Arabia.
    Naeem, M.A.
    Chemical Engineering Department, University of the Punjab, Lahore 54000, Pakistan.
    Mahmood, Asif
    College of Engineering Chemical Engineering Department King Saud University Riyadh, Saudi Arabia.
    Ramay, Shahid M.
    Department of Physics and Astronomy, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
    Spinel-type Na2MoO4 and Na2WO4 as promising optoelectronic materials: First-principle DFT calculations2020Ingår i: Chemical Physics, ISSN 0301-0104, E-ISSN 1873-4421, Vol. 538, artikel-id 110902Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The mechanical, thermodynamic, electronic, and optical properties of Na2MoO4 (NMO) and Na2WO4 (NWO) spinels are elaborated by density functional theory (DFT) based full potential augmented plane wave method (FP-LAPW + lo). Our optimized lattice constants for the studied spinels are in good agreement with that obtained experimentally. The enthalpy of formation ensures the thermodynamic stability of NMO and NWO in the cubic phase. The Born mechanical stability criteria guarantees their mechanical stability, while Poisson ratio (ν) and Pugh's ratio (B/G) infer their brittle behavior. The Debye temperature (θD) is significant for NMO than NWO. The wide bandgap of 3.5 eV for NMO and 4.4 eV for NWO show the maximum absorption in the ultraviolet region that increases their importance for optoelectronic applications. The optical properties are explained in term of dielectric constant, refractive index, absorption of light, reflection, and optical loss factor.

  • 49.
    Abbas, Zainab Dekan
    et al.
    Environmental Department, Urban Planning College, Kufa University, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Jassim, Osama
    Environmental Department, Urban Planning College, Kufa University, Iraq.
    Locating Dam Sites For Water Harvesting: Case Study Of Najaf Province, Iraq2019Ingår i: Journal of Environmental Hydrology, ISSN 1058-3912, E-ISSN 1996-7918, Journal of Environmental Hydrology, ISSN 1058-3912, Vol. 27, s. 1-8, artikel-id 10Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Middle East is considered as an arid area. Iraq was an exception due to the presence of the Tigris  and  Euphrates  Rivers. After  1970,  the  flow  of  these  rivers  started  to  decrease  due  to  climate change  and  building  of  dams  in  the  upper  parts  of  the  catchments  of  the  rivers.  Now,  Iraq  is experiencing  water  shortage  problems.  Rain  water  harvesting  will  definitely  minimize  the  effect  of water shortage problems. In this research an arid area was selected (al Najaf) to find out the best sites for water harvesting using GIS techniques. The good agreement between the results from a simple GIS model  and  observations  in  cases  such  as  al  Najaf  Sea  is  indicating  a  promising  future  for  GIS application  in  hydrological  modeling.  The  present  study  proposed  a  function  formula  of  estimating suitable dam site using existing geographic information map such as the digital elevation maps. It is expected that it will save time, cost and work force. Finally, through the contour map of the study area, the lowest three elevation values at the governorate level were observed (20, 40, 60m). Based on these values, three possibilities were suggested to select the dam sites.

    Ladda ner fulltext (pdf)
    fulltext
  • 50.
    Abbasi, Hamon
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Velayat park: En plats för gränsöverskridande möten mellan människor med olika socioekonomisk status2017Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

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

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

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

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

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

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

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

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

    Ladda ner fulltext (pdf)
    fulltext
1234567 1 - 50 av 52363
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf