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  • 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.
    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

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    FULLTEXT01
  • 4.
    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

  • 5.
    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.

  • 6.
    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.

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    FULLTEXT01
  • 7.
    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.

  • 8.
    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)
  • 9.
    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.

  • 10.
    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

  • 11.
    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.

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  • 12.
    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
  • 13.
    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
  • 14.
    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.

  • 15.
    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
  • 16.
    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)
  • 17.
    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

  • 18.
    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

  • 19.
    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.

  • 20.
    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.

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  • 21.
    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.

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  • 22.
    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.

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  • 23.
    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.

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    Climate Change Impacts on Water Resources of Greater
  • 24.
    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.

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  • 25.
    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.

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  • 26.
    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.

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  • 27.
    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.

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  • 28.
    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.

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  • 29.
    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.

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  • 30.
    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.

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  • 31.
    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.

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  • 32.
    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.

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  • 33.
    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.

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    Khabour
  • 34.
    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.

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  • 35.
    Abbott, Daniel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    The architectural design of Swedish live-work premises: A case study on live-work premises and its potential2021Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    En pandemi har tvingat många att arbeta hemifrån och mixad arbetsmiljön med bostadsmiljön. Frågan är om detta fungerar? Ett relativt ungt koncept baserat på ett uråldrigt är “bokaler”. Bokaler är ett koncept där bostaden integreras och lever i symbios med arbetet. Bokaler som koncept involverar mer än bara hemmakontor. Arbetet ifråga är i konceptet inte begränsat till det man redan kan utföra i bostaden utan inkluderar även traditionella serviceyrken. Efter ett år med nya arbetsförhållanden var det många som vill behålla möjligheten att kunna arbeta hemifrån men samtidigt har det varit en del som har rapporterat missnöje med arbetsförhållandet. Med denna plötsliga nya trend ska denna rapport då undersöka vilka design metoder som bör utföras för att designa en “god” arbetsplats som lever i symbios med en “god” bostad, det vill säga en “god” bokal.

    Denna studie inleder även med en hypotes att bokaler även kan hjälpa när det kommer till att skapa mer tryggare och attraktiva städer. Då trygghet och attraktivitet förknippas med blandstaden som myntas både av arkitekter och kommunfolk. Möjligheten att etablera bokaler och se hur ett sådant koncept passar in i Sveriges städer ska också undersökas.

    Undersökningen är baserat på en fallstudiemetod där det empirin kommer från nuvarande användare utav bokaler, arkitekter, stadsplanerare och andra sakkunniga. Samt kommer även teorier om hur man skapar goda miljöer jämföras med existerande bokaler. Fallstudien jobbar även ihop med en designmetod där man använder som argument för designval. Studien använder detta för att se om överväganden om hur bokaler ska designas kan replikeras och är sanna.

    Studien lyckades få tag en handfullägare utav bokaler (tio stycken), fem arkitekter och analysera sex olika typologier utav bokaler. Resultatet visade att det oftast var otroligt trångt att få in alla kvaliteter som önskas i en arbetsmiljö, respektive bostadsmiljö. Eftersom bokaler är alltid placerat i bottenplan upplever användare en otrygghet och en utsatthet för stadsmässiga besvärligheter. Arkitekter påpekar även det finns en del lagstiftande element som förhindrar konceptet att blomstra till fullo samt att det även kan finnas kulturella och samhällsmässigabegränsningar. Exempelvis taxeras arbetsplatser och bostäder olika ochnär man har en symbios av dessa blir det svårt att avgöra vad som ska gälla. Sedan är det även så att samhället i Sverige är designat att gynna störreföretag och inte de mindre företag somskulle använda bokaler. Att börja etablera små företag i ett bostadsområde skulle innebära en stor risk för dessa bokalägare.

    Det kom alltså fram till att man måste överväga tre saker när man designaren bokal för att den ska kunna frodas i ett svenskt samhälle. Dessa tre överväganden var sedan även testade på ett område och projekt i Luleå. Funktionerna (bostads- och arbetsfunktioner) ska helst inte beblandas i bostaden, detta för att man ska kunna separera för att undvika konflikter ochför att trivseln i bokalen ska höjas. Bokalen bör vara flexibel och ha möjlighet att kunna anpassa sig för förändringar och olika funktioner.Man behöver tänka sig för hur man förhåller sig till resten av staden. Bokalens placering i staden är viktigt för att den ska överleva, men även föratt de som bor i bokalen ska trivas bör organisationen av hur funktioner placeras i bokalen reflekteras över. Att bokalen kan bidra till attraktivt samhälle är svårt att avgöra innan man ser att bokaler kan faktiskt frodas i vårt samhälle. Möjligheten att uppnå social kontroll med bokaler fungerari teorin men det behöver undersökas ytterligare.

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  • 36.
    Abbu, Muthanna
    et al.
    Building and Construction Engineering Deptartment, Northern Technical University, Mosul, Iraq.
    Al-Attar, Alyaa A.
    Building and Construction Engineering Deptartment, Northern Technical University, Mosul, Iraq.
    Abd Alrahman, Saad
    Building and Construction Engineering Deptartment, Northern Technical University, Mosul, Iraq.
    Al-Gburi, Majid
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    The mechanical properties of lightweight (volcanic pumice) concrete containing fibers with exposure to high temperatures2023Ingår i: Journal of the Mechanical Behavior of Materials, ISSN 2191-0243, Vol. 32, nr 1, artikel-id 20220249Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fires are considered one of the main risks leading to building collapse. Lightweight concrete comprises a variety of components, each of which has a distinct behavior under the effect of temperature change. A total of sixteen concrete mixtures were investigated in this paper. A reference mix of concrete comprising simply ordinary Portland cement and ten mixes having varying percentages of fine and coarse lightweight aggregates (pumice), which were replaced gravel and sand by fine pumice and coarse aggregates pumice by 20%, 40%, 60%, 80%, and 100%, respectively. In addition, the study focused on the effects of adding fibers to lightweight aggregate concrete mixtures. Polypropylene fibers, carbon fibers, and steel fibers were employed as fiber additions. The binary mixture had higher density than the remaining mixtures containing one substitute. The behavior of six concrete mixes in addition to the reference mix of ordinary concrete after exposure to temperatures 100, 250, 350 and 450 °C for two hours and then cooled in two ways (water and air) as well as examined directly and the results showed that the concrete mixes containing fiber better behavior compared to other mixtures, especially at high temperature. If left to cool in the air, the lightweight concrete containing Volcanic Pumice can recover its compression strength after being exposed to high temperatures.

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  • 37.
    Abdeldjouad, Lokmane
    et al.
    EVRNZA Laboratory, University of Ouargla, Ouargla, Algeria; Department of Civil and Hydraulic Engineering, Faculty of Applied Sciences, University of Ouargla, Ouargla, Algeria.
    Dheyab, Wisam
    Department of Civil Engineering, College of Engineering, Tikrit University, Tikrit, Iraq.
    Gamil, Yaser
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Department of Civil Engineering, School of Engineering, Monash University Malaysia, Selangor, Malaysia.
    Asadi, Afshin
    EnvoGéotechnique Ltd, Auckland, New Zealand.
    Shukla, Sanjay Kumar
    Geotechnical and Geoenvironmental Engineering Research Group, School of Engineering, Edith Cowan University, Joondalup, Perth, WA 6027, Australia.
    Thermal curing effects on alkali-activated treated soils with palm oil fuel ash2023Ingår i: Case Studies in Construction Materials, E-ISSN 2214-5095, Vol. 19, artikel-id e02455Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Regarding the significance of binder quantity, alkali activator molarities, and thermal curing, this work was utilized to geopolymerize with a potassium-based alkaline activator to strengthen soils. Five different molarities of palm oil fuel ash (POFA) in four different amounts were utilized to activate the clayey soil. POFA admixtures have been used to test soils. The results showed that for mixtures with 10 and 12.5 molarities, the unconfined compressive strength (UCS) with 15 % and 20 % of POFA was stronger. Comparing the strengths of the blends with various POFA amounts and concentration molarities allowed for this determination. To increase the strength, it is crucial to consider how the geopolymerization method's temperature and curing time affect the UCS of the soil-POFA mixture with and without fibers. The UCS of the treated soil mixtures was changed by heating at 30, 50, 70, and 90 degrees C. The outcomes demonstrate that increasing the curing temperature will hasten the alkaline activation process. After seven days of heating, the treated soil specimens with and without fibers exhibit the best mechanical properties at a healing temperature of about 70 degrees C, with compressive strengths of 16.7 and 11.4 MPa. The interaction between the geo-polymeric matrix and the fiber surface, the molarities of the alkaline solution, and the heating temperature were the most important aspects, according to an investigation of the microstructures, in improving the behavior of the reinforced mixes. By offering an efficient approach for increasing the qualities of soil treated by the alkali activation of POFA through the inclusion of glass fibers with adequate molarities of reagent and cure heating temperature, the current work offers new insights into soil stabilization operations. This has advantages over conventional calcium-based binders due to their emission of carbon dioxide during manufacture, which is one of the major causes of global warming.

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  • 38.
    Abdel-Hameed, Amal Mohamed
    et al.
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza, 12613, Egypt.
    Abuarab, Mohamed
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza, 12613, Egypt.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Sayed, Hazem
    Irrigation and Drainage Department, Agricultural Engineering Research Institute, Giza, 12613, Egypt.
    Kassem, Mohamed A.
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza, 12613, Egypt.
    Elbeltagi, Ahmed
    Agricultural Engineering Department, Faculty of Agriculture, Mansoura University, Mansoura, 35516, Egypt.
    Mokhtar, Ali
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza, 12613, Egypt; School of Geographic Sciences Key Lab. of Geographic Information Science (Ministry of Education), East China Normal University, Zhongshan, China.
    Estimation of Potato Water Footprint Using Machine Learning Algorithm Models in Arid Regions2024Ingår i: Potato Research, ISSN 0014-3065, E-ISSN 1871-4528Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Precise assessment of water footprint to improve the water consumption and crop yield for irrigated agricultural efficiency is required in order to achieve water management sustainability. Although Penman-Monteith is more successful than other methods and it is the most frequently used technique to calculate water footprint, however, it requires a significant number of meteorological parameters at different spatio-temporal scales, which are sometimes inaccessible in many of the developing countries such as Egypt. Machine learning models are widely used to represent complicated phenomena because of their high performance in the non-linear relations of inputs and outputs. Therefore, the objectives of this research were to (1) develop and compare four machine learning models: support vector regression (SVR), random forest (RF), extreme gradient boost (XGB), and artificial neural network (ANN) over three potato governorates (Al-Gharbia, Al-Dakahlia, and Al-Beheira) in the Nile Delta of Egypt and (2) select the best model in the best combination of climate input variables. The available variables used for this study were maximum temperature (Tmax), minimum temperature (Tmin), average temperature (Tave), wind speed (WS), relative humidity (RH), precipitation (P), vapor pressure deficit (VPD), solar radiation (SR), sown area (SA), and crop coefficient (Kc) to predict the potato blue water footprint (BWF) during 1990–2016. Six scenarios (Sc1–Sc6) of input variables were used to test the weight of each variable in four applied models. The results demonstrated that Sc5 with the XGB and ANN model gave the most promising results to predict BWF in this arid region based on vapor pressure deficit, precipitation, solar radiation, crop coefficient data, followed by Sc1. The created models produced comparatively superior outcomes and can contribute to the decision-making process for water management and development planners. 

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  • 39.
    Abdel-Hameed, Amal Mohamed
    et al.
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza 12613, Egypt.
    Abuarab, Mohamed EL-Sayed
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza 12613, Egypt.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Mehawed, Hazem Sayed
    Irrigation and Drainage Department, Agricultural Engineering Research Institute, Giza 12613, Egypt.
    Kassem, Mohamed Abdelwahab
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza 12613, Egypt.
    He, Hongming
    School of Geographic Sciences, East China Normal University, Shanghai 210062, China.
    Gyasi-Agyei, Yeboah
    School of Engineering and Built Environment, Griffith University, Nathan, QLD 4111, Australia.
    Mokhtar, Ali
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza 12613, Egypt; School of Geographic Sciences, East China Normal University, Shanghai 210062, China.
    Winter Potato Water Footprint Response to Climate Change in Egypt2022Ingår i: Atmosphere, ISSN 2073-4433, E-ISSN 2073-4433, Vol. 13, nr 7, artikel-id 1052Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The limited amount of freshwater is the most important challenge facing Egypt due to increasing population and climate change. The objective of this study was to investigate how climatic change affects the winter potato water footprint at the Nile Delta covering 10 governorates from 1990 to 2016. Winter potato evapotranspiration (ETC) was calculated based on daily climate variables of minimum temperature, maximum temperature, wind speed and relative humidity during the growing season (October–February). The Mann–Kendall test was applied to determine the trend of climatic variables, crop evapotranspiration and water footprint. The results showed that the highest precipitation values were registered in the northwest governorates (Alexandria followed by Kafr El-Sheikh). The potato water footprint decreased from 170 m3 ton−1 in 1990 to 120 m3 ton−1 in 2016. The blue-water footprint contributed more than 75% of the total; the remainder came from the green-water footprint. The findings from this research can help government and policy makers better understand the impact of climate change on potato crop yield and to enhance sustainable water management in Egypt’s major crop-producing regions to alleviate water scarcity.

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  • 40.
    Abdel-Khalek, N.A.
    et al.
    Central Metallurgical Research and Development Institute (CMRDI), PO Box 87, Helwan, Cairo, Egypt.
    Yassin, K.E.
    Central Metallurgical Research and Development Institute (CMRDI), PO Box 87, Helwan, Cairo, Egypt.
    Selim, K. A.
    Central Metallurgical Research and Development Institute (CMRDI), PO Box 87, Helwan, Cairo, Egypt.
    Rao, Kota Hanumantha
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Kandel, A.-H.
    Chemistry Department Faculty of Science, Helwan University, Helwan, Egypt.
    Effect of starch type on selectivity of cationic flotation of iron ore2012Ingår i: Mineral Processing and Extractive Metallurgy: Transactions of the Institutions of Mining and Metallurgy: Section C, ISSN 0371-9553, E-ISSN 1743-2855, Vol. 121, nr 2, s. 98-102Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 41.
    Abdollahi, Morteza
    et al.
    Faculty of Engineering, Urmia University, Iran.
    Bahrami, Ataallah
    Department of Mining Engineering, Faculty of Engineering – Urmia University, P.O. Box 57561/51818, Iran.
    Saleh Mirmohammadi, Mir
    School of Mining Engineering, University of Tehran, Iran.
    Kazemi, Fatemeh
    Faculty of Engineering – University of Kashan, Iran.
    Danesh, Abolfazl
    Complex of Copper Processing – Sungun, Headquarters Rd, Tabriz, East Azerbaijan Province, Iran.
    Ghorbani, Yousef
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi.
    A process mineralogy approach to optimize molybdenite flotation in copper: molybdenum processing plants2020Ingår i: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 157, artikel-id 106557Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Sungun copper-molybdenum operation in Iran uses a typical copper-molybdenum flowsheet to produce separate copper and molybdenum concentrates through flotation and regrinding of the rougher concentrates arising from the primary circuit. This site was used as a case study limited to the feed and products of the copper-molybdenum separation circuit, in which process mineralogy might improve the quality of the molybdenum concentrate thorough diagnostic analysis of key flowsheet streams. The undesirable presence of copper in the molybdenum concentrate was identified as a key focus for the investigation by process mineralogy, which has a history of successful process diagnosis. This is because it develops information on minerals, which is far more informative than chemical assays alone. Together with the assays, the mineralogical data inform the investigator of the type and quantity of minerals present, their state of liberation and textural associations, and metal recovery.

    A key finding was that the appearance of chalcopyrite in the molybdenum concentrate was due to the presence of a chalcopyrite-pyrite texture that avoided the chalcopyrite depression in the molybdenum circuit because of suitable pyrite flotation conditions. Recovery of liberated pyrite to this concentrate also diluted the molybdenum concentrate. The open-circuit format of the regrind circuit also contributed to the unnecessary production of ultrafine particles. This flaw expressed itself as ultrafine losses of molybdenite to the flotation tailings.

  • 42.
    Abdollahpour, N.
    et al.
    Department of Ergonomics, University of Social Welfare and Rehabilitation Science, Tehran.
    Helali, Faramarz
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle.
    Hoseini, M.A.
    Department of Rehabilitation Management, University of Social Welfare and Rehabilitation Science, Tehran.
    Ghomshe, F. Tabatabaei
    Department of Industrial Engineering, Institute for Higher Education of Kar, Qhazvin.
    Ziarani, M. Hamzeiyan
    Department of Industrial Engineering, Institute for Higher Education of Kar, Qhazvin.
    Peysepar, S.
    HSE Unit of MAPNA Turbine Blade Engineering and Manufacturing Company-PARTO, Karaj.
    An improving working condition system (health, safety and ergonomics) survey and analysis with macroergonomics approach in a manufacturing company from Iran Power Plant Industry in 20102013Ingår i: Iran Occupational Health, ISSN 1735-5133, E-ISSN 2228-7493, Vol. 10, nr 4, s. 55-64Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 43.
    Abdollahpour, Nosrat
    et al.
    Department of Occupational Health, School of Health, Tabriz University of Medical Sciences, Tabriz.
    Dastranj, Farahnaz
    Occupational Health, International Campus of Shahid Sadoughi University of Medical Sciences (IC-SSUMS) Yazd – Iran.
    Helali, Faramarz
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Arbetsvetenskap.
    Ziarani, M. Hamzeian
    Zeiaei, M.
    Stress Prevention at Work Checkpoints: Practical improvements for stress prevention the workplace2016 (uppl. Free)Bok (Övrig (populärvetenskap, debatt, mm))
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  • 44.
    Abdollahpour, Nosrat
    et al.
    Department of Occupational Health Engineering, Tabriz University of Medical Sciences Tabriz, Iran.
    Helali, Faramarz
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Arbetsvetenskap.
    Implementing 'Awakened Need of Change' for Applying Ergonomics to Work System with Macroergonomics Approach in an Industrially Derveloping Country and its Meta-Reflection2016Ingår i: Journal of Ergonomics, E-ISSN 2165-7556, Vol. 6, nr 6, artikel-id 182Artikel i tidskrift (Refereegranskat)
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  • 45.
    Abdollahpour, Nosrat
    et al.
    Department of Occupational Health Engineering and Ergonomics, Tabriz University of Medical Sciences, Tabriz, Iran.
    Helali, Faramarz
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Implementing Practical Ergonomics Knowledge Transfer Using Ergonomic Checkpoints to Support the Participatory Ergonomics Process in an Industrially Developing Country2022Ingår i: IISE Transactions on Occupational Ergonomics and Human Factors, ISSN 2472-5838, Vol. 10, nr 2, s. 59-70Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Implementing ergonomics principles in workplaces requires good knowledge transfer with the participation of professionals, workers, and managers.

    Purpose: This study aimed to investigate practical ergonomics knowledge transfer to support the participatory ergonomics process that could lead problem identification and the implementation and development of feasible and low-cost solutions.

    Methods: This was action research on the type of intervention and conducted in four phases. Accordingly, 106 participants from different organizational levels of a manufacturing company, facilitated by an ergonomist by forming 14 action groups, were involved in practical ergonomics knowledge transfer to identify and solve problems of work divisions. Participant reflections were obtained through interviews and field notes.

    Results: The results contributed to the presentation of 145 solutions to improve working conditions by the action groups. Most solutions were low-cost and 57.5% were implemented. The interviews showed the development of a participation culture, learning and institutionalizing ergonomics principles in practice, and improving competence in identifying problems and implementing solutions.

    Conclusions: The key findings were achieved by the participatory ergonomics intervention approach through different tactics of participant engagement, including a pushing tactic for intentional learning and a pulling tactic for voluntary learning, which resulted in the improvement of working conditions and promotion of a participatory culture.

  • 46.
    Abdollahpour, Nosrat
    et al.
    Department of Occupational Health and Ergonomics, Faculty of Health, Tabriz University of Medical Sciences, Tabriz, Iran.
    Helali, Faramarz
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Rasoulzadeh, Yahya
    Department of Occupational Health and Ergonomics, Faculty of Health, Tabriz University of Medical Sciences, Tabriz, Iran; Iranian Traffic Injuries Research Centre, Tabriz University of Medical Sciences, Tabriz, Iran.
    Hassankhani, Hadi
    Centre of Qualitative Studies, Department of Medical Surgical Nursing, School of Nursing and Midwifery, Tabriz University of Medical Sciences, Tabriz, Iran.
    Barriers and Challenges to Human Factors/Ergonomics Knowledge Transfer to Small Business Enterprises in an Industrially Developing Country2023Ingår i: IISE Transactions on Occupational Ergonomics and Human Factors, ISSN 2472-5838, Vol. 11, nr 1-2, s. 14-31Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OCCUPATIONAL APPLICATION

    We found that small business enterprises (SBEs) face intra- and extra-organizational barriers in different dimensions related to their work system to practically implement human factors/ergonomics (HFE) knowledge transfer and to achieve its benefits in an industrially developing country. Utilizing a three-zone lens, we evaluated the feasibility of overcoming the barriers identified by stakeholders, especially ergonomists. To overcome the identified barriers in practice, three types of macroergonomics interventions (top-down, middle-out, and bottom-up) were distinguished through macroergonomics theory. The bottom-up approach of macroergonomics, as a participatory HFE intervention, was considered as the entry point to overcome the perceived barriers in the first zone of the lens, which included such themes as lack of competence, lack of involvement and interaction, and inefficient training and learning approaches. This approach focused on improving emotional literacy as a care zone among the small business enterprise personnel.

    TECHNICAL ABSTRACT

    Background: The human factors/ergonomics (HFE) knowledge transfer process is one of the potential challenges for organizations in industrially developing countries (IDCs), especially in small business enterprises (SBEs).

    Purpose: We explored perceived barriers and challenges to the practical implementation of HFE knowledge transfer to SBEs in Iran, as an IDC, to improve their work systems.

    Methods: An exploratory qualitative study was conducted using a conventional content analysis. To identify perceived barriers, we conducted individual interviews (n = 38) and a focus-group discussion (n = 17) with the participation of the SBEs personnel and the officials of related organizations. Inductive content analysis was used for data analysis. We then categorized the identified perceived barriers (themes) to determine the feasibility of overcoming them.

    Results: Regarding perceived barriers, the following nine themes were extracted: lack of competence, resistance to change, technological infrastructure problems, lack of involvement and interaction, using an inappropriate mode of knowledge, lack of culture-building about HFE, inefficient training and learning approaches, lack of scientific management, and extra-organizational problems. Further, a three-zone lens was identified for the extracted themes to check the feasibility of overcoming them.

    Conclusions: We identified nine intra- and extra-organizational barriers in the HFE knowledge transfer process to SBEs. We further evaluated the ways of overcoming perceived barriers defined in the three-zone lens to adapt them for building creative workplace culture zones (care, creative, and improvement). We distinguished three types of macroergonomics interventions (top-down, middle-out, and bottom-up) and three supporting strategies, including, knowledge, management and employees, and participatory HFE.

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  • 47.
    Abdollahpour, Nosrat
    et al.
    Department of Occupational Health, School of Health, Ardabil University of Medical Sciences, Ardabil.
    Helali, Faramarz
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Arbetsvetenskap.
    Ziaei, M
    Department of Occupational Health, School of Health, Shiraz University of Medical Sciences, Shiraz.
    Hamzeian, M
    Department of Ergonomics, University of Social Welfare and Rehabilitation Science, Tehran.
    Keikhamoghadam, AA
    Department of Occupational Health, School of Health, Tabriz University of Medical Sciences, Tabriz.
    Gholamnia, R
    Department of Occupational Health Engineering, School of Health, Safety and environment, Shahid Beheshti University of Medical Sciences, Tehran.
    Ghaffari, A
    HSE Unit of National Iranian Gas Company, Tehran, Iran.
    Assessment of risk factors and the prevalence of musculoskeletal disorders by QEC and Body Map operational units of the gas refinery in Iran and its Meta-Reflection2016Ingår i: Journal of Health, ISSN 2382-9710, Vol. 7, nr 1, s. 35-50, artikel-id 7Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

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  • 48.
    Abdulhameed, Ali A.
    et al.
    Department of Reconstruction and Projects, University of Baghdad, Baghdad 10071, Iraq.
    Hason, Mahir M.
    Disaster Information Management Centre, Ministry of Science and Technology, Baghdad 10071, Iraq.
    Sharba, Amjad Ali K.
    Department of Civil Engineering, Mustansiriya University, Baghdad, Iraq.
    Hanoon, Ammar N.
    Department of Reconstruction and Projects, University of Baghdad, Baghdad 10071, Iraq.
    Amran, Mugahed
    Department of Civil Engineering, College of Engineering, Prince Sattam Bin Abdulaziz University, 11942 Alkharj, Saudi Arabia.; Department of Civil Engineering, Faculty of Engineering and IT, Amran University, 9677 Amran, Yemen.
    Magbool, Hassan M.
    Civil Engineering Department, College of Engineering, Jazan University, Jazan, Saudi Arabia.
    Gamil, Yaser
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Department of Civil Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
    Experimental and environmental investigations of the impacts of wood sawdust on the performance of reinforced concrete composite beams2023Ingår i: Case Studies in Construction Materials, E-ISSN 2214-5095, Vol. 19, artikel-id e02550Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It has been established that using recycled materials to replace some of the fine aggregates is a viable solution. Most researchers focused on the durability aspect of wood sawdust concrete, while less information is available on its structural performance. Therefore, this article aimed to investigate the performance of reinforced concrete beams fabricated from concrete with a partially replaced fine aggregate (FA) by wood sawdust (WS) in the range of 5–45 % (by weight). Six beams underwent 4-point bending tests till collapse. The beams' slump, density, compressive strength, cracking and failure mode, energy absorption, and economic and environmental aspects were studied. The findings showed that the failure region of sawdust concrete was more significant than the reference samples. Despite the compressive strength of the concrete containing different ratios of sawdust being reduced by about 7–30 %, the target compressive strength still has a limit of low to normal concrete grade. The results show that the increase in sawdust percentages decreased the acquired absorbed energy of the subjected load to reach failure. A cost reduction of 9 % and a cost index of 61 % is achieved using wooden sawdust-based concrete. By substituting sawdust for fine aggregate, the sustainability of sawdust concrete in terms of cost and environmental advantages may be improved. In addition, it is well-known that harnessing the transformative potential of industrial waste in concrete production not only minimizes landfill usage, but also promotes resource efficiency, reduces carbon emissions, and advances the circular economy, propelling designers, engineering and builders towards a greener and more sustainable future in the construction industry. According to the test findings, wood sawdust may be utilized to produce normal and low-strength structural concrete.

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  • 49.
    Abdulhameed, Isam Mohammed
    et al.
    University of Anbar, College of Engineering, Upper Euphrates Basin Developing Centre, Ramadi, Iraq.
    Sulaiman, Sadeq Oleiwi
    University of Anbar, College of Engineering, Dams and Water Resources Department, Ramadi, Iraq.
    Ahmed Najm, Abu Baker
    University of Anbar, College of Engineering, Dams and Water Resources Department, Ramadi, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Optimising water resources management by Using Water Evaluation and Planning (WEAP) in the West of Iraq2022Ingår i: Journal of Water and Land Development, ISSN 1429-7426, nr 53, s. 176-186Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Iraq has been suffering from decreasing Euphrates discharge due to the construction of dams within upstream countries and the use of surface irrigation systems. The country is facing a problem with meeting the increasing demand for water as a result of population growth and development in the industrial and agricultural sectors. Therefore, a simulation modelling was applied for western Iraq (Ramadi city as a case study) using the Water Evaluation and Planning System (WEAP) for the period 2018–2035. This research follows a four-step approach that involves: (i) evaluating the available water of the Euphrates River under declined water imports caused by the construction of dams in Turkey and Syria, (ii) assessing present and future water demands of the domestic, industrial, and agricultural sectors, (iii) improving water productivity (WP) by means of saving more water, (iv) estimating the economic returns under improved water use. The results showed that Iraq would face a serious problem in the coming years, represented by the limited storage of Haditha Dam, which is considered the strategic water storage site for the central and southern regions of Iraq. The study indicated the necessity of finding alternative sources of water supply by adopting new water management strategies to reduce the water deficit. 

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  • 50.
    Abdul-Jalbar, Beatriz
    et al.
    Dpto. de Matemáticas, Estadística e Investigación Operativa, Universidad de La Laguna, Spain.
    Segerstedt, Anders
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Industriell Ekonomi.
    A note on “A new heuristic for one warehouse and N retailers problem” by Ercan Senyigit and Hakan Akkan in Procedia - Social and Behavioral Sciences, 62, p. 656 – 660, 20122019Manuskript (preprint) (Övrigt vetenskapligt)
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