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  • 151.
    Alizadeh Noghani, Kyoomars
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Hernandez Benet, Cristian
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Kassler, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Marotta, Antonio
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Jestin, Patrick
    Ericsson AB, Sweden.
    Srivastava, Vivek V.
    Ericsson AB, Sweden.
    Automating Ethernet VPN deployment in SDN-based Data Centers2017In: 2017 Fourth International Conference on Software Defined Systems (SDS)., IEEE, 2017, p. 61-66Conference paper (Refereed)
    Abstract [en]

    Layer 2 Virtual Private Network (L2VPN) is widely deployed in both service provider networks and enterprises. However, legacy L2VPN solutions have scalability limitations in the context of Data Center (DC) interconnection and networking which require new approaches that address the requirements of service providers for virtual private cloud services. Recently, Ethernet VPN (EVPN) has been proposed to address many of those concerns and vendors started to deploy EVPN based solutions in DC edge routers. However, manual configuration leads to a time-consuming, error-prone configuration and high operational costs. Automating the EVPN deployment from cloud platforms such as OpenStack enhances both the deployment and flexibility of EVPN Instances (EVIs). This paper proposes a Software Defined Network (SDN) based framework that automates the EVPN deployment and management inside SDN-based DCs using OpenStack and OpenDaylight (ODL). We implemented and extended several modules inside ODL controller to manage and interact with EVIs and an interface to OpenStack that allows the deployment and configuration of EVIs. We conclude with scalability analysis of our solution.

  • 152.
    Alizadeh Noghani, Kyoomars
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Hernandez Benet, Cristian
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Taheri, Javid
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    SDN helps volume in Big Data2018In: Big Data and Software Defined Networks / [ed] Javid Taheri, London: IET Digital Library, 2018, 1, p. 185-206Chapter in book (Refereed)
    Abstract [en]

    Both Big Data and SDN are described in detail in previous chapters. This chapter investigates how SDN architecture can leverage its unique features to mitigate the challenges of Big Data volume. Accordingly, first, we provide an overview of Big Data volume, its effects on the underlying network, and mention some potential SDN solutions to address the corresponding challenges. Second, we elaborate more on the network-monitoring, traffic-engineering, and fault-tolerant mechanisms which we believe they may help to address the challenges of Big Data volume. Finally, this chapter is concluded with some open issues.

  • 153.
    Alizadeh Noghani, Kyoomars
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Kassler, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    SDN Enhanced Ethernet VPN for Data Center Interconnect2017In: 2017 IEEE 6th International Conference on Cloud Networking (CloudNet) / [ed] Maga, D, IEEE, 2017, p. 77-82Conference paper (Refereed)
    Abstract [en]

    Ethernet Virtual Private Network (EVPN) is an emerging technology that addresses the networking challenges presented by geo-distributed Data Centers (DCs). One of the major advantages of EVPN over legacy layer 2 VPN solutions is providing All-Active (A-A) mode of operation so that the traffic can truly be multi-homed on Provider Edge (PE) routers. However, A-A mode of operation introduces new challenges. In the case where the Customer Edge (CE) router is multi-homed to one or more PE routers, it is necessary that only one of the PE routers should forward Broadcast, Unknown unicast, and Multicast (BUM) traffic into the DC. The PE router that assumes the primary role for forwarding BUM traffic to the CE device is called the Designated Forwarder (DF). The proposed solution to select the DF in the EVPN standard is based on a distributed algorithm which has a number of drawbacks such as unfairness and intermittent behavior. In this paper, we introduce a Software-Defined Networking (SDN) based architecture for EVPN support, where the SDN controller interacts with EVPN control plane. We demonstrate how our solution mitigates existing problems for DF selection which leads to improved EVPN performance.

  • 154.
    Alizadeh Noghani, Kyoomars
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Kassler, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Sankar Gopannan, Prem
    Ericsson, USA.
    EVPN/SDN Assisted Live VM Migration between Geo-Distributed Data Centers2018In: 4th IEEE Conference on Network Softwarization (NetSoft), IEEE, 2018, p. 105-113Conference paper (Refereed)
    Abstract [en]

    Live Virtual Machine (VM) migration has significantly improved the flexibility of modern Data Centers (DC). However, seamless live migration of a VM between geo-distributed DCs faces several challenges due to difficulties in preserving the network configuration after the migration paired with a large network convergence time. Although SDN-based approaches can speed up network convergence time, these techniques have two limitations. First, they typically react to the new topology by installing new flow rules once the migration is finished. Second, because the WAN is typically not under SDN control, they result in sub-optimal routing thus severely degrading the network performance once the VM is attached at the new location.

    In this paper, we identify networking challenges for VM migration across geo-distributed DCs. Based on those observations, we design a novel long-haul VM migration scheme that overcomes those limitations. First, instead of reactively restoring connectivity after the migration, our SDN-based approach proactively restores flows across the WAN towards the new location with the help of EVPN and VXLAN overlay technologies. Second, the SDN controller accelerates the network convergence by announcing the migration to other controllers using MP-BGP control plane messages. Finally, the SDN controller resolves the sub-optimal routing problem that arises as a result of migration implementing a distributed anycast gateway. We implement our approach as extensions to the OpenDaylight controller. Our evaluation shows that our approach outperforms existing approaches in reducing the downtime by 400 ms and increasing the application performance up to 12 times.

  • 155.
    Alizadeh Noghani, Kyoomars
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Kassler, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Taheri, Javid
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    On the Cost-Optimality Trade-off for Service Function Chain Reconfiguration2019Conference paper (Refereed)
    Abstract [en]

    Optimal placement of Virtual Network Functions (VNFs) in virtualized data centers enhances the overall performance of Service Function Chains (SFCs) and decreases the operational costs for mobile network operators. Maintaining an optimal placement of VNFs under changing load requires a dynamic reconfiguration that includes adding or removing VNF instances, changing the resource allocation of VNFs, and re-routing corresponding service flows. However, such reconfiguration may lead to notable service disruptions and impose additional overhead on the VNF infrastructure, especially when reconfiguration entails state or VNF migration. On the other hand, not changing the existing placement may lead to high operational costs. In this paper, we investigate the trade-off between the reconfiguration of SFCs and the optimality of the resulting placement and service flow (re)routing. We model different reconfiguration costs related to the migration of stateful VNFs and solve a joint optimization problem that aims to minimize both the total cost of the VNF placement and the reconfiguration cost necessary for repairing a suboptimal placement. Numerical results show that a small number of reconfiguration operations can significantly reduce the operational cost of the VNF infrastructure; however, too much reconfiguration may not pay off should heavy costs be involved.

  • 156.
    Alizadeh Noghani, Kyoomars
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Kassler, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Taheri, Javid
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Öhlen, Peter
    Ericsson AB.
    Curescu, Calin
    Ericsson AB.
    On the Cost-Optimality Trade-off for Fast Service Function Chain ReconfigurationManuscript (preprint) (Other academic)
    Abstract [en]

    Optimal placement of Virtual Network Functions (VNFs) in data centers enhances the overall performance of Service Function Chains (SFCs) and decreases the operational costs for mobile network operators. In order to cope with changes in demands, VNF instances may be added or removed dynamically, resource allocations may be adjusted, and servers may be consolidated. To maintain an optimal placement of SFC under changing conditions, dynamic reconfiguration is required including the migration of VNFs and the re-routing of service flows. However, such reconfiguration may lead to notable service disruptions and can be exacerbated when reconfiguration entails state or VNF migration, both imposing additional overhead on the VNF infrastructure. On the other hand, not changing the placement may lead to a suboptimal operation, servers and links may become congested or underutilized, leading to high operational costs. In this paper, we investigate the trade-off between the reconfiguration of SFCs and the optimality of the resulting placement and service flow routing. We model reconfiguration costs related to the migration of stateful VNFs and solve a joint optimization problem that aims to minimize both the total cost of the new placement and the reconfiguration cost necessary to achieve it. We also develop a fast multi-objective genetic algorithm that finds near-optimal solutions for online decisions. Our numerical evaluations show that a small number of reconfiguration operations can significantly reduce the operational cost of the VNF infrastructure. In contrast, too much reconfiguration may not pay off due to high costs. We believe that our work is an important tool that helps network provider to plan a good reconfiguration strategy for their service chains.

  • 157.
    Al-Jaff, Mohammed
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    The ZX-Calculus: A graphical calculus for multipartite qubit systems2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis we will give a presentation of a graphical/diagrammatic calculus for quantum systems involving interacting quantum observables such as multi-partite systems of qubits, the ZX-Calculus. Unlike the Hilbert space formulation of quantum mechanics, the ZX-Calculus is based on category theory, more specically on the notion of a compact dagger symmetric monoidal category and as a consequence the graphical language associated with such a category is inherited by the calculus. This enables us to think about and deal with many calculations in quantum computation and information in a purely graphical and intuitive fashion. Although being formulated in a more general mathematical framework, huge parts of the Hilbert space formulation of quantum mechanics can be extracted from the ZX-calculus. In this thesis we will begin by giving a motivation for the need of such a calculus and then key concepts of category theory will be introduced in an intuitive manner in order to understand the ZX-calculus that will be presented afterwards. We then apply the calculus to'model' and describe certain quantum circuits and quantum teleportation.

  • 158.
    Aljinovic, Andrea Aglic
    et al.
    University of Zagreb, Croatia.
    Peric, Ivan
    University of Zagreb, Croatia.
    Persson, Lars-Erik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Josip Pecaric- and his life in mathematics and politics2019In: Mathematical Inequalities & Applications, ISSN 1331-4343, E-ISSN 1848-9966, Vol. 22, no 4, p. 1067-1080Article in journal (Refereed)
    Abstract [en]

    It is impossible in limited number of pages to give a fair picture of such a remarkable man, great mathematician and human being as Josip Pecaric. Our intention is instead to complement the picture of him in various ways. We hope that our paper will give also someflavor of Josip as family man, fighter, supervisor,international authority, author (also in other subjects than mathematics), fan of the Croatian football team, and not only as his obvious role as our King of Inequalities.

  • 159.
    Allard, Gabriella
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
    Gustafsson, Alexander
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
    Närståendes upplevelser när en familjemedlem eller någon i närkretsen lever med HIV/AIDS - En litteraturstudie2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I världen är det idag 30-35 miljoner människor som lever med HIV/AIDS och i Sverige lever idag 6 500 människor med HIV. Den HIV-drabbade är inte den enda som drabbas, då även de närstående drabbas av sjukdomens påfrestningar. Syftet med litteraturstudien var att beskriva närståendes upplevelser när en familjemedlem eller någon i närkretsen lever med HIV/AIDS. Metoden var litteraturstudie, som genomfördes med Polit och Becks niostegsmodell. Artikelrsökningen genomfördes på databaserna CINAHL och PubMed. De artiklar som inkluderades i litteraturstudien gick igenom en urvalsprocess med inklusionkriterier och granskningsmallar. Det var 11 artiklar som behölls efter urvalsprocessen med sex kvalitativa, tre kvantitativa och två med blandad metod. Resultatet är uppdelat i två huvudkategorier Emotioner samt Psykisk belastning. Underkategorierna var frustration/ilska, rädsla/oro, hopp och hopplöshet, sorg/besvikelse respektive stigmatisering, ansvar/brist på stöd samt stress. Slutsats: Dessa olika upplevelser påverkar den närstående negativt på olika sätt och kan medföra ohälsa och försämrad livskvalitet hos de närstående. Ytterligare forskning behövs.

  • 160.
    Allard, Marie-Louise
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Bilen, ett tekniskt system: 3-åringars uppfattning kring bilen som ett tekniskt system och dess komponenter2014Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the survey is to find out what perception children in preschool have about the car as a technical system, how its components interact, and also their perception on various components of the traffic system. Qualitative interviews were conducted with eleven children in the age of three about their experiences on this.

     

    The result shows that most of the children in the study have experience on the components that are most prominent on a car such as steering wheel, wheels and engine. The results are mixed in terms of knowledge of the components' importance and how they interact with each other. The survey also shows that the children who have the greatest knowledge of the components' importance are those who have been with an adult when changing tires, refueling, minor repairs, etc. According to the results, most of the kids know that there must be roads to drive on and they recognize for example traffic lights and Mr. Gårman plate available at pedestrian crossings. However, there is general uncertainty about the significance of them.

  • 161.
    Alm, Anton
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Internet of Things mesh network: Using the Thread networking protocol2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis summarizes my project in setting up a Thread network. The idea of this project was presented by the company ÅF in Karlstad, Sweden. ÅF wishes to upgrade their current demonstrator for IoT. The current demonstrator includes Azure Cloud component, Raspberry Pi, Bluetooth and Arduino components. The upgrade includes implementing Thread technology together with Thread verified hardware from Nordic semiconductor and the Raspberry Pi Foundation.

    Thread is an IoT mesh networking protocol that was released year 2014. Compared to Bluetooth it offers IP communication (including IPv6) combined with higher reliability, performance and security. The process of installing, compiling and configuring the Thread network is explained.

    The result is an operational thread network that has sensor devices sending data to an HTTP web server, where the data is stored and monitored. Though, there are many improvements and functions that can be implemented to make this demonstrator more appealing.

  • 162.
    Almani, T.
    et al.
    Austin, USA.
    Kumar, Kundan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). University of Bergen, Norway.
    Singh, G.
    Austin, USA.
    Wheeler, M. F.
    Austin, USA.
    Stability of multirate explicit coupling of geomechanics with flow in a poroelastic medium2019In: Computers and Mathematics with Applications, ISSN 0898-1221, E-ISSN 1873-7668, Vol. 78, no 8, p. 2682-2699Article in journal (Refereed)
    Abstract [en]

    We consider single rate and multirate explicit schemes for the Biot system modeling coupled flow and geomechanics in a poro-elastic medium. These schemes are widely used in practice that follows a sequential procedure in which the flow and mechanics problems are fully decoupled. In such a scheme, the flow problem is solved first with time-lagging the displacement term followed by the mechanics solve. The multirate explicit coupling scheme exploits the different time scales for the mechanics and flow problems by taking multiple finer time steps for flow within one coarse mechanics time step. We provide fully discrete schemes for both the single and multirate approaches that use Backward Euler time discretization and mixed spaces for flow and conformal Galerkin for mechanics. We perform a rigorous stability analysis and derive the conditions on reservoir parameters and the number of finer flow solves to ensure stability for both schemes. Furthermore, we investigate the computational time savings for explicit coupling schemes against iterative coupling schemes.

  • 163.
    Almani, T.
    et al.
    Saudi Arabian Oil Company (Aramco), Saudi Arabia.
    Manea, A.
    Saudi Arabian Oil Company (Aramco), Saudi Arabia.
    Kumar, Kundan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). University of Bergen, Norway.
    Dogru, A. H.
    Saudi Arabian Oil Company (Aramco), Saudi Arabia; MIT, USA.
    Convergence of the undrained split iterative scheme for coupling flow with geomechanics in heterogeneous poroelastic media2019In: Computational Geosciences, ISSN 1420-0597, E-ISSN 1573-1499Article in journal (Refereed)
    Abstract [en]

    Recently, an accurate coupling between subsurface flow and reservoir geomechanics has received more attention in both academia and industry. This stems from the fact that incorporating a geomechanics model into upstream flow simulation is critical for accurately predicting wellbore instabilities and hydraulic fracturing processes. One of the recently introduced iterative coupling algorithms to couple flow with geomechanics is the undrained split iterative coupling algorithm as reported by Kumar et al. (2016) and Mikelic and Wheeler (Comput. Geosci. 17: 455–461 2013). The convergence of this scheme is established in Mikelic and Wheeler (Comput. Geosci. 17:455–461 2013) for the single rate iterative coupling algorithm and in Kumar et al. (2016) for the multirate iterative coupling algorithm, in which the flow takes multiple finer time steps within one coarse mechanics time step. All previously established results study the convergence of the scheme in homogeneous poroelastic media. In this work, following the approach in Almani et al. (2017), we extend these results to the case of heterogeneous poroelastic media, in which each grid cell is associated with its own set of flow and mechanics parameters for both the single rate and multirate schemes. Second, following the approach in Almani et al. (Comput. Geosci. 21:1157–1172 2017), we establish a priori error estimates for the single rate case of the scheme in homogeneous poroelastic media. To the best of our knowledge, this is the first rigorous and complete mathematical analysis of the undrained split iterative coupling scheme in heterogeneous poroelastic media.

  • 164.
    Almlöf Ambjörnsson, Heléne
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Mercerization and Enzymatic Pretreatment of Cellulose in Dissolving Pulps2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis deals with the preparation of chemically and/or enzymatically modified cellulose. This modification can be either irreversible or reversible. Irreversible modification is used to prepare cellulose derivatives as end products, whereas reversible modification is used to enhance solubility in the preparation of regenerated cellulose.

    The irreversible modification studied here was the preparation of carboxymethyl cellulose (CMC) using extended mercerization of a spruce dissolving pulp. More specifically the parameters studied were the effect of mercerization at different proportions of cellulose I and II in the dissolving pulp, the concentration of alkali, the temperature and the reaction time. The parameters evaluated were the degree of substitution, the filterability and the amount of gel obtained when the resulting CMC was dissolved in water. Molecular structures of CMC and its gel fractions were analysed by using NIR FT Raman spectroscopy. It was found that the alkali concentration in the mercerization stage had an extensive influence on the subsequent etherification reaction. FT Raman spectra of CMC samples and their gel fractions prepared with low NaOH concentrations (9%) in the mercerization stage indicated an incomplete transformation of cellulose to Na-cellulose before carboxymethylation to CMC. Low average DS values of the CMC, i.e. between 0.42 and 0.50 were obtained. Such CMC dissolved in water resulted in very thick and semi solid gum-like gels, probably due to an uneven distribution of substituents along the cellulose backbone. FT Raman spectra of CMC samples and their gel fractions mercerized at higher alkaline concentration, i.e. 18.25 and 27.5% in the mercerization stage, indicated on the other hand a complete transformation of cellulose to Na-cellulose before carboxymethylation to CMC. Higher average DS values of the CMC, i.e. between 0.88 and 1.05 were therefore obtained. When dissolved in water such CMC caused gel formation especially when prepared from dissolving pulp with a high fraction of cellulose II.

    The reversible modification studied was the dissolution of cellulose in NaOH/ZnO. Here the effect of enzyme pretreatment was investigated by using two mono-component enzymes; namely xylanase and endoglucanase, used in consecutive stages. It was found that although the crystallinity and the specific surface area of the dissolving pulp sustained minimal change during the enzymatic treatment; the solubility of pulp increased in a NaOH/ZnO solution from 29% for untreated pulp up to 81% for enzymatic pretreated pulp.

  • 165.
    Almlöf Ambjörnsson, Heléne
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Östberg, Linda
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Schenzel, Karla
    Martin Luther University Halle-Wittenberg, Department of Natural Scinence III, Institute of Agriculture and Nutritional Science.
    Larsson, Per Tomas
    Innventia AB, Fibre and Material Science Business area Biorefining, Stockholm.
    Germgård, Ulf
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Enzyme pretreatment of dissolving pulp as a way to improve the following dissolution in NaOH/ZnO2014In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 68, no 4, p. 385-391Article in journal (Refereed)
  • 166. Almotasem, Ahmed
    et al.
    Bergström, Jens
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Gåård, Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Krakhmalev, Pavel
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Holleboom, Thijs Jan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    A molecular dynamic study on the influence of carbide particles in ferrite on material transfer during nanoscratching of ferritic iron2016In: Proceedings of the 10th International Tool Conference: TOOL, 10th International TOOL Conference : 04th to 07th October 2016, Bratislava, Slovakia / [ed] Simancik, Frantisek, 2016Conference paper (Refereed)
  • 167.
    AlMotasem, Ahmed Tamer
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Bergström, Jens
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Gåård, Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Krakhmalev, Pavel
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Holleboom, Thijs Jan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Adhesion between ferrite iron-€“iron/cementite countersurfaces: A molecular dynamics study2016In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 103, p. 113-120Article in journal (Refereed)
    Abstract [en]

    The adhesive properties of Fe(110)/Fe(110) and Fe3C(001)/Fe(110) countersurfaces have been investigated by using classical molecular dynamics simulations. The simulation results show that Fe3C/Fe exhibits a relatively lower adhesion compared to the Fe/Fe. Additionally, the temperature dependence of the adhesive properties between 300–700 K has been examined. The results demonstrate that, with increasing the temperature, the values of the adhesion force and the work of adhesion continuously decrease in the case of Fe3C/Fe; they initially slightly increase up to 500 K then decrease in the case of Fe/Fe. Furthermore, the effect of lattice coherency between Fe/Fe has been examined and found to slightly reduce the adhesion. These results explain how carbides improve galling resistance of tool steel observed during dry sliding. 

  • 168.
    AlMotasem, Ahmed Tamer
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Department of Physics, Faculty of ScienceAssiut University Assiut Egyp.
    Bergström, Jens
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Gåård, Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Krakhmalev, Pavel
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013), Science, Mathematics and Engineering Education Research.
    Holleboom, Thijs Jan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Atomistic insights on the wear/friction behavior of nanocrystalline ferrite during nanoscratching as revealed by molecular dynamics2017In: Tribology letters, ISSN 1023-8883, E-ISSN 1573-2711, Vol. 65, no 3, p. 101-Article in journal (Refereed)
    Abstract [en]

    Using embedded atom method potential, extensive large-scale molecular dynamics (MD) simulations of nanoindentation/nanoscratching of nanocrystalline (nc) iron have been carried out to explore grain size dependence of wear response. MD results show no clear dependence of the frictional and normal forces on the grain size, and the single-crystal (sc) iron has higher frictional and normal force compared to nc-samples. For all samples, the dislocation- mediated mechanism is the primary cause of plastic deformation in both nanoindentation/nanoscratch. However, secondary cooperative mechanisms are varied significantly according to grain size. Pileup formation was observed in the front of and sideways of the tool, and they exhibit strong dependence on grain orientation rather than grain size. Tip size has significant impact on nanoscratch characteristics; both frictional and normal forces monotonically increase as tip radii increase, while the friction coefficient value drops by about 38%. Additionally, the increase in scratch depth leads to an increase in frictional and normal forces as well as friction coefficient. To elucidate the relevance of indentation/scratch results with mechanical properties, uniaxial tensile test was performed for nc-samples, and the result indicates the existence of both the regular and inverse Hall-Petch relations at critical grain size of 110.9 angstrom. The present results suggest that indentation/scratch hardness has no apparent correlation with the mechanical properties of the substrate, whereas the plastic deformation has.

  • 169.
    AlMotasem, Ahmed Tamer
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013). Assiut University, Egypt.
    Bergström, Jens
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Gåård, Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Krakhmalev, Pavel
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Holleboom, Thijs Jan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Tool microstructure impact on the wear behavior of ferrite iron during nanoscratching: An atomic level simulation2017In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 370-371, p. 39-45Article in journal (Refereed)
    Abstract [en]

    In the present work, molecular dynamics simulations were used to investigate the impact of the tool microstructure on the wear behavior of ferrite workpiece during nanoscratching. The tool microstructure was modified by varying the carbide (cementite) contents. The simulation results show that dislocations are the primary mechanism for plastic deformation of the workpiece material. It is found that total dislocation length varies significantly depending on the carbide content in the tool. Furthermore, other tribological phenomena were also observed to depend on the carbide contents. For example, the average value of frictional forces decreased while the normal force increases with increasing carbide contents, and hence the friction coefficient was decreased. Additionally, the shape and size of lateral and frontal pileups are lowered. The structural analysis of the pileup region reveals the loss of long range order and start of amorphisation. The temperature distribution of the pileup regions showed an increase of the pileup temperature when carbide is added into tool. The wear volume is considerably reduced when the carbide content increases. The average scratch hardness was found to decrease and the result was analyzed with the theoretical Taylor hardening model.

  • 170.
    AlMotasem, Ahmed Tamer
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Gåård, Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Influence of chemical composition on adhesion in metallic contacts2016In: International Journal of Advances in Science Engineering and Technology, ISSN 2321-9009, Vol. 4, no 3, Spl. Iss. 1, p. 229-231Article in journal (Refereed)
    Abstract [en]

    - In sheet metal forming operations, adhesive wear is the main causeof tool damage as sheet material is transferred to the tool surface during the forming operation. Means of reducing adhesive wear are of high interest for the metal forming industry.In the present work, molecular dynamics simulations were used to investigate influence of alloying iron with vanadium on adhesive properties in contact with iron. The results showed that adhesion, quantified by the work of adhesion, decreased as the vanadium content increased. Highest reduction was obtained for 10 at.% vanadium which corresponded to a decrease in adhesive work of approximately 10%.

  • 171.
    AlMotasem, Ahmed Tamer
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Posselt, Matthias
    Helmholtz Zentrum Dresden-Rossendorf, Germany.
    Bergström, Jens
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Nanoindentation and nanoscratching of a ferrite/austenite iron bi-crystal: An atomistic study2018In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 127, p. 231-239Article in journal (Refereed)
    Abstract [en]

    Molecular dynamics simulations are applied to investigate the wear/friction behavior of a ferrite/austenite iron bi-crystal, as a model system for duplex stainless steels. The plasticity of the ferrite phase is dominated by dislocations while both dislocations and stacking faults are the primary cause of plastic deformation of the austenite phase. Interestingly, the responses of tribological parameters vary depending on the scratch direction. For instance, the scratch hardness is increased by about 46% whereas the friction coefficient is reduced by about 22% when scratch starts from austenite to ferrite. At the interface, a local softening/hardening occurs because of dislocation-interface interaction. The present results demonstrate that martensitic phase transformation is responsible for experimentally observed high amount of ferrite of the pile-up.

  • 172.
    Almqvist, Kjerstin
    et al.
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies (from 2013).
    Bäccman, Charlotte
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies (from 2013).
    Anderzen-Carlsson, Agneta
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Norlén, Anna
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies (from 2013). Ericastiftelsen.
    Pernebo, Karin
    FoU Kronoberg, Region Kronoberg; Institutionen för Psykologi, Linnéuniversitetet.
    Massoudi, Pamela
    Institutionen för Psykologi, Linnéuniversitetet.
    iRiSk II: Utveckling av bedömningsinstrument och stödinsatser för våldsutsatta barn - rapport fråm två delprojekt2018Report (Other academic)
  • 173.
    Almqvist, Kjerstin
    et al.
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies (from 2013).
    Källström, Åsa
    Örebro universitet.
    Appell, Petra
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Social and Psychological Studies (from 2013).
    Anderzen-Carlsson, Agneta
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013). Örebro universitet.
    Mothers’ opinions on being asked about exposure to intimate partner violence in child healthcare centres in Sweden2018In: Journal of Child Health Care, ISSN 1367-4935, E-ISSN 1741-2889, Vol. 22, no 2, p. 228-237Article in journal (Refereed)
    Abstract [en]

    Intimate partner violence (IPV) constitutes a hidden health risk for exposed mothers and children. In Sweden, screening for IPV in healthcare has only been routine during pregnancy, despite an increase in IPV following childbirth. The arguments against routine questions postpartum have concerned a lack of evidence of beneficial effects as well as fear of stigmatizing women or placing abused women at further risk. Increased understanding of women’s attitudes to routine questions may allay these fears. In this study, 198 mothers in 12 child healthcare centres (CHCs) filled in a short questionnaire about their exposure and received information on IPV at a regular baby check-up visit. The mothers’ lifetime prevalence of exposure to IPV was 16%. One hundred and twenty-eight mothers participated in a telephone interview, giving their opinion on the screening experience. The intervention was well-received by most of the mothers who reported that questions and information on IPV are essential for parents, considering the health risks for children, and that the CHC is a natural arena for this. Necessary prerequisites were that questioning be routine to avoid stigmatizing and be offered in privacy without the partner being present.

  • 174.
    Almqvist, Ylva
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Kan en lärare hinna med alla elever i dagens matematikundervisning?: En intervjustudie av hur lärare beskriver undervisningen av elever som presterar lågt i matematik.2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this study I want to illustrate how teachers describe their preventions and interventions when teaching students with low achievement in mathematics. This is a qualitative study based on a series of group interviews of teachers in the Swedish compulsory school. Mathematics teachers still hold a traditional compensatory perspective on students with low achievement thus placing the responsibility for learning with the students. The general opinion is that special pedagogics is necessary to enable support enough to help students with low achievement in mathematics to reach a passing grade. Thanks to further training, primarily through “Matematiklyftet”, the view on the possibility to include low achieving students in the classroom in a good way is more positive. There is an ongoing work in schools to improve the mathematics teaching, but one cannot see a complete or common plan for the schools neither from the school administration nor the teachers. The preventive measures made to include the low achieving students does have a positive effect for all students. Much of the implemented changes have its origin in talking mathematics in the classroom and not following the textbook as slavishly as previously done.

  • 175.
    Almssad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Betongkonstruktion2015Book (Other academic)
    Abstract [sv]

    Betongkonstruktion behandlar dimensionering och utförande av betongkonstruktioner enligt Eurocode 2. Boken består av en teoridel som innefattar:• Böjning och böjning med normalkraft• Pelare och väggar• Genomstansning• Plattor• Beräkning i bruksgränstillståndet

    Bokens konkreta pedagogiska värden är, utöver ett stort antal övnings­exempel med lösningar och svar, ett avsnitt med utvecklande övningsuppgifter som studenterna kan lösa själva.Svaren till dessa uppgifter finns i boken och utförliga lösningsförslag finns att tillgå på webben, www.studentlitteratur.se/39041.

  • 176.
    Almssad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Betongkonstruktion: Formelsamling2016Book (Other academic)
    Abstract [sv]

    Ett komplement till boken Betongkonstruktion. Formelsamlingen är framtagen för att användas som hjälpmedel vid examination i högskole- och universitetskurser inom betongkonstruktion.

  • 177.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Almusaed, Amjad
    Archcrea Institute.
    Bio-Ecological Sustainable Windows2005In: The International Conference Sustainable Building 2005 SB05, Tokyo: SB05Tokyo National Conference Board , 2005, p. 31-34Conference paper (Refereed)
    Abstract [en]

    Window is a vital part of any house they permit natural light into the house as long as views and fresh air. In the same time we can consider that the window is an extremely influential factor in climatic design, as the weakest climatic element of the building envelope. Well designed and protected windows improve comfort year round and reduce the need for heating in winter and cooling in summer. Aesthetics appearance, view, and optical performance, are usually quite important to the occupant. In reality, the serious lighting designer cannot take any notice of the energy implications of window choices. New technologies help to resolve the historic problem of the transaction between windows that reflect unwanted solar gains in the summer and those that admit a maximum quantity of useful light. Well-designed windows and shading devices allow solar heat gain in winter and shade and ventilation in summer while providing enough day lighting. Solar gain achieved by heaving 60% of the building’s windows orientated correctly can reduce the heating load of  house by _22%.In houses, low solar heat gain coefficient glazing should be used on east and west orientations, while high glazing should be used when passive solar and day lighting are being utilized.

    Today’s window technologies can replace more primitive strategies for shielding interior spaces from unwanted sunlight, such as tinted windows and curtains.

  • 178.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Almusaed, Amjad
    Archcrea Institute.
    Efficient daylighting approach by means of light-shelve device adequate for habitat program in Aarhus City2014In: International Journal of Smart Grid and Clean Energy, ISSN 2315-4462, Vol. 3, no 4, p. 441-453Article in journal (Refereed)
    Abstract [en]

    The concepts of light shelves consist of windows that have face towards the sun, which receive a vast quantity of energy that could be used for healthy day lighting. This paper debates a main assessment, investigates the optimization of daylight requirement by means of light shelves system. An experimental test was carried out assessing the measurements and lighting simulations of a model of a building in order to elucidate the characteristics of indoor lighting. Light shelf is an architectural element that permits daylight to enter deep into a building. It constitutes an optimal solution for an incorrect building orientation and less sunny days. The essential objective of this study is to highlight the vital role of light shelves in residential buildings in northern Europa where the requirement is to improve the daylight in the interior functional spaces. The main objects of this paper are to investigate the effect of daylight in the interior functional spaces using light shelves, the effect of natural light diffusion in interior space in the period of low daylight season, and glare effect in this field. This paper investigates a procedure for analysing the daylight performance using software habitat function

  • 179.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Almusaed, Amjad
    Albasrah University, Albasrah, Iraq.
    Environmental reply to vernacular habitat conformation from a vast areas of Scandinavia2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 48, p. 825-834Article in journal (Refereed)
    Abstract [en]

    There are many original ideas and useful system inputs embedded in the building of human settlements in Scandinavian regions, where the landscape and habitat are strongly interconnected. A cold climate and strong winds are the most prominent risks that affect habitats. The Longhouse is the foremost traditional habitat in the Scandinavian region, dating back to the Iron Age, 2000 BC. This study examines the influence of climate on the conformation of habitats. Climate had a solid impact on the conceptions of habitat form and internal space. Wind and extreme temperatures had firming consequences on the housing arrangements, layouts, orientations, and building materials used in the construction process. Habitats from this region were located in an optimal arrangement, and the south orientation was used effectively. This investigation will provide an evaluative interpretation and analysis of the real facts of vernacular habitats in the context of energy efficiency and ecological concepts, considering human settlement patterns, architectural creation and building material uses. (C) 2015 Elsevier Ltd. All rights reserved.

  • 180.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Almusaed, Amjad
    Archcrea Institute.
    Green housing: The optimal Solution To Combat The Negative Effects Of Global Climatechange2010In: 3rd International Conference Palenc 2010 jointly organised with EPIC 2010 & 1st Cool Roofs Conference, University of Athens, Greece , 2010Conference paper (Refereed)
    Abstract [en]

    No Architectural concept is complete without green areas. The vital mission of biophilic architecture is to revised conceptualization of architecture in response to a myriad of contemporary concerns about the effects of human activity. Our earth is warming more rapidly than it has in the past according to the research of scientists. The green building of biophilic architecture combines the interests of sustainability, environmental consciousness, green areas of the large nature, and organic approaches to evolve design solutions from these requirements and from the characteristics of the site, its neighborhood context, and the local microclimate and topography. The biophilic concept provides us with the opportunity to reach extremely low levels of energy consumption by employing high quality, cost-efficient measures to general architectural components - such measures are in turn off advantage to the ecology and economy sector. Our essential task of this research is to make of the green covering a human strategy in urban and architectural manner and to be a human culture with helping of local governments; we can acquire the competent legislation, which protect our life and environment.

  • 181.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Almusaed, Amjad
    Jönköping universitet / Department of Construction Engineering and Lighting Science.
    Housing Policy Matters2018In: Housing / [ed] Amjad Almusaed & Asaad Almusaed, London: Intechopen , 2018Chapter in book (Refereed)
    Abstract [en]

    This book is proposed as both a general reading of the discipline for students in architecture and urban planning, and offers a variety of materials for professionals of local and international organizations. It brings together studies with new perspectives and relevant subjects from different geographical areas. The book gathers the contributions of international researchers and experts. It is divided into three parts and eight chapters: Part I, "Introduction to Housing Affairs," includes a chapter that discusses a general reading of housing as meaning and action in social, economic, and environmental city life. Part II, "Case Studies Upon Housing Policies," includes four chapters. It consists of many examples from different geographical areas and domains. Part III, "Housing Quality and Affordability," includes three chapters; housing quality, sustainability, and development are the main subjects for this part.

  • 182.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Almusaed, Amjad
    Jönköping University.
    Overview of a Competent Sustainable Building2018In: Sustainable Buildning: Interaction Between a Holistic Conceptual Act and Materials Properties / [ed] Amjad Almusaed & Asaad Almssad, London: InTech, 2018, p. 3-16Chapter in book (Refereed)
    Abstract [en]

    This book has been written to represent the efficient applications of sustainability upon building designs. The book intends to illustrate various techniques of action of sustainability on building conceptions. The book is divided into four parts and eight chapters. Part I "Introduction into Target Theme" includes a chapter with title "Introductory Chapter." It makes an overview of the meaning and the target of sustainable building and sustainable building material. Part II "Sustainable Building Design, Process, and Management" discusses many forms and concepts of sustainable building and includes three chapters. Part III "Sustainable Building by Using Energy Efficiency in Building Design" includes one chapter. Part IV "Sustainability in Building Materials: Study Cases" includes three chapters.

  • 183.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Almusaed, Amjad
    Archcrea Institute.
    Kalil Almusaed, Zaki
    Heat Island Effects Upon The Human Life On The City Of Basrah2007In: Building Low Energy Cooling and Advanced Ventilation Technologies in the 21st Century: 2nd PALENC Conference 28th AIVC Conference / [ed] M. Santamouris, P. Wouters, Crete island: University of Athens , 2007, p. 45-47Conference paper (Refereed)
    Abstract [en]

    After the terrible consequence of the Iraq –Iran war and recently USA attack over Iraq the urban green covering disappeared from large areas of the city, beside the extension of the building over the green areas. The negative effects of this phenomenon over human’s thermal comfort become more perceptive. Today we can observe clearly the negative effect of urban heat island in the center of Basra city, precisely in physical frameworks of the city; we can observe a typical phenomenon with a large negative effect for the period of summer heating that is a natural thermodynamic phenomenon. In the surfaces of physical framework, in the core of day between 12-15 pm, the sun is shining perpendicular above the earth surfaces (framework physic). Consequently the temperature on the earth surfaces increases surprisingly up to 60 ºC. Therefore there occurs a difference of temperature between the earth surfaces and cosmos space which conduce to generate a gigantic colonization of air from the earth surface to cosmos space, such resultants of this phenomenon is no air zones and under pressure on earth surfaces, with the intention of making a nasal bleeding, which seeking for a medical intervention aide.

  • 184.
    Almstedt, Lisa
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Karlsson, Elin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Patienters erfarenheter i samband med amputation av nedre extremitet: En litteraturstudie2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 185.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Bioclimatic Interpretation Over Vernacular Houses From Historical city Basrah.2006In: PLEA 2006: 23rd International Conference on Passive and Low Energy Architecture., Geneve: Universite de Geneve , 2006, p. 87-91Conference paper (Refereed)
    Abstract [en]

    Basrah’s climate is hot, dry summer, mild to cold winter, and a pleasant spring and fall. The old builders from this region putted a big effort to create passive bioclimatic houses that corresponds the negative effects Basrah’s macroclimate. The courtyard is the central and dominant space in the house plan with a direct access to the living spaces. Houses from the city are compact with interior courtyard; the streets are sinuous and pass through houses volumes. The shady interior courtyard has the effect that the rooms do not communicate directly with the overheated air outside, but through intermediate buffer spaces. In the mean time between courtyard and street at least a wall or a building is always interposed. The House plan had an endomorphic form, (open tree form). The volumes were concept to create shadow which helps to move the air by natural movement to the deep superior side, that can be achieve through special holes. The architectural elements are strongly decorated, reproducing special typologies and traditional houses. Open spaces, covered by large roofs, are interesting due to the mix of diffuse light and shade that are an essential aesthetic factor in these buildings.

  • 186.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Building materials in eco-energy houses from Iraq and Iran2015In: Case Studies in Construction Materials, ISSN 2213-624X, E-ISSN 2214-3998, Vol. 1, p. 42-54Article in journal (Refereed)
    Abstract [en]

    Builders from the Western part of Asia are trained to make buildings that can fulfil certain required functions while giving full consideration to all sites and environmental conditions. The research covers the zone between Iraq and Iran. The first investigated region is the ‘‘Mesopotamian Marshes’’ or Iraqi-Iran Marshes, a wetland zone situated in southern Iraq and partially in southwestern Iran. The other region is a desert district, which includes a prominent part of the southern and western parts of Iraq and part of Iran. The last is the centre city of Basra. The building materials were the most important building element that affected the conformation of vernacular habitats from the western part of Asia in general and the Iraq–Iran area in particular. In this study, we needed to focus on the effects of ecological and energy-efficiency processes in creating vernacular habitats and the selection of optimal building systems and materials in this part of the world, which can be an essential point for sustainable environmental building processes in the future. Reeds, clay, straw, bricks, and wood were the most popular building materials used by builders from this region. The impact of building material on the environment embodies the essential method implicitly significant in this research to effectively determine traditional building materials in the environment, in addition to comparative analysis. This presents an essential factor of our analysis, in addition to the impact of environments on building systems. The main target of this study is to benefit designers and building engineers in their pursuit to find optimal and competent solutions suitable for specific local microclimates using traditional methods in the design process that are sustainable and ecological.

  • 187.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, AsaadKarlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Insulation Materials in Context of Sustainability2016Collection (editor) (Refereed)
  • 188.
    Almusaed, Amjad
    et al.
    Basra University, Iraq.
    Almssad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Alasadi, Asaad
    Basra University, Iraq.
    Analytical interpretation of energy efficiency concepts in the housing design process from hot climate2019In: Journal of Building Engineering, ISSN 2352-7102, Vol. 21, p. 254-266Article in journal (Refereed)
    Abstract [en]

    The classical understanding of an architectural product shows architecture as a series of complex activities, which aims to create an optimal material framework with well-organized functional spaces that can meet the material and human spiritual requirements. The vision of a multifaceted architecture shows that it is necessary to design and work cooperatively with an architectural theory to transform the lateral conceptual viewer of the multilateral design process. The effort has to focus on ensuring the active collaboration of sciences and techniques with the creative building design process. The real stages of house design theory still insufficiently incorporate natural phenomena such as thermography, climatology, aerodynamics, and thermodynamics in the building design approach. The primary target of this research is to define an efficient method of building design in which essential aspects are considered during the first phase of design ideas. The study concluded that using a classical design model is respectable. However, it can bring many mistakes in the confirmation of a holistic design assignment related to energy, thermal comfort, and economic factors that represents an essential tool for architectural creation products where the innovative model proceeds with all design elements, activities and space roles which can reunify in the interpretation of functional spaces by creating an interspace with a consistency habitat environment.

  • 189.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Almusaed, Ali
    Towards a Zero Energy House Strategy Fitting For South Iraq climate2008In: Passive and Low Energy Architecture 2008 Conference / [ed] Paul Kenny, Vivienne Brophy, J. Owen Lewis, Dublin: University College Dublin , 2008, p. 40-44Conference paper (Refereed)
  • 190. Almusaed, Amjad
    et al.
    Almusad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Natural Lighting Efficiency By Means of Sun- Skylight-Tubes2014In: International Journal of Engineering and Advanced Technology, ISSN 2249-8958, E-ISSN 2249-8958, Vol. 3, no 3, p. 16-20Article in journal (Refereed)
    Abstract [en]

    The notion of comfort a luminous ambience refers to the distribution of luminance and chromatic ties on the interior envelope of a space that is one of different fields of vision for a subject within an ambience. Luminance and chromatic ties are at present not often studied as far as comfort in buildings is concerned. Sun lighting and bioclimatic concept is inseparable considerations when designing a building because of the historical and practical significance of natural lighting in architecture. Sunlight is as old as architecture itself. Human life gets sufficient sunlight, in fact, we use more of 90 % of our day indoor, for this reason, specialists are now seeing how architecture can ameliorate the indoor-outdoor links. At present, by biological and technological investigation the trend is to search backwards towards the previous philosophies and advantages of more indoor / outdoor relationship. Plus homeowners who want to have healthy home environments might want to renew the most relevant facts of technology and biology.

  • 191.
    Almén, Anton
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Importance of atomic force microscopy settings for measuring the diameter of carbon nanotubes2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Carbon nanotubes (CNTs) have gathered a lot of interest because of their extraordinary mechanical, electrical and thermal properties and have potential applications in a wide variety of areas such as material-reinforcement and nano-electronics. The properties of nanotubes are dependent on their diameter and methods for determining this using atomic force microscopy (AFM) in tapping mode assume that the measured height of the tubes represent the real diameter. Based on early, faulty calculations, the forces in tapping mode were assumed to be much lower than in contact mode, however it was later shown that forces in tapping mode can at point of impact rival the forces present in contact mode. This means that there is a potential risk of tube deformation during tapping mode measurements, resulting in incorrectly determined diameters. This work studies CNTs deposited on a silicon-substrate to analyze the effect of three common AFM settings (tapping frequency, free oscillation amplitude and setpoint) to determine their effect on measured CNT diameters and recommendations for choosing settings are given.

  • 192.
    Alpmarken, Ia
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Studie av tekniska och ekonomiska fördelar av olika lösningar vid instrumentinstallation2015Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Inom industrin är tendensen att allt mer arbete automatiseras för snabbare, mer kostnadseffektiv samt exaktare tillverkning eller bearbetning. Vid automatisering av en processindustri möts konstruktören av ett flertal utmaningar, i minst att välja vilken installationsmetod som skall användas i det aktuella fallet.Vid en ombyggnation eller tillbyggnad av en existerande processindustri finns ofta begränsningar som styr vilken installationsmetod som kan användas, kunden kan exempelvis önska att den nya installationen utförs på liknande sätt som den tidigare.En nyinstallation kan däremot ge att konstruktören har möjlighet att själv påverka installationsmetod.

    I samarbete med Sweco Industry, ett konsultbolag som bland annat ägnar sig åt att konstruera system för processtyrning åt kunder, samt Valmet, ett företag som konstruerar anläggningar för tillverkning av mjukpapper, har därför en studie utförts för att studera vilken typ av installation som är mest kostnadseffektiv för ett uppbyggt typfall.

    Detta har utförts genom att planera fem installationer för det uppbyggda fallet och jämföra dess delkostnader samt totalkostnader.

    Den installationsmetod som påvisat lägst totalkostnad är en installation med distribuerade I/O-moduler anslutna till styrsystemet via PROFIBUS DP fältbuss.

    Trots en något högre totalkostnad rekommenderas dock en installation medelst fältinstrument anslutna till en fältbuss av lägre nivå då detta medför en störningssäker kommunikation och ger en tidseffektiv installation.

  • 193.
    Alsharoa, A.
    et al.
    University of Central Florida.
    Ghazzai, Hakim
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Yuksel, M.
    University of Central Florida.
    Kadri, A.
    Qatar Mobility Innovations Center (QMIC), Qatar University.
    Kamal, A. E.
    Iowa State University (ISU), Ames.
    Trajectory optimization for multiple UAVs acting as wireless relays2018In: 2018 IEEE International Conference on Communications Workshops, ICC Workshops 2018 - Proceedings, IEEE, 2018, p. 1-6Conference paper (Refereed)
    Abstract [en]

    This paper proposes a novel wireless relay selection scheme involving multiple mobile Unmanned Aerial Vehicles (UAVs) to support communicating ground users. The goal is to optimize the transmit power levels and trajectories of the relaying UAVs in order to maximize the data rate transmission of the ground users which are suffering from the absence of direct link. Assuming that each UAV is initially characterized by a predefined trajectory for a primary task, we propose to modify it whenever it is needed and the energy and trajectory boundaries constraints allow. We propose to solve this problem using an iterative two steps solution; first, a Mixed Integer Linear Programming (MILP) problem is formulated to optimally determine the users- UAVs associations and the UAVs' corresponding transmit power levels. In the second step, an efficient algorithm based on a recursive shrink-and-realign process is proposed to optimize the UAV trajectories. The performance of the proposed method shows advantages in terms of average throughput compared to the predefined trajectories solution.

  • 194.
    Altersved, Karin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Wallén, Agneta
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Patienters upplevelse av oral hälsa vid diagnosen erosiv oral lichen planus: En kvalitativ studie2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 195.
    Alubusi, Sara
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Munhygienvanor och kunskap om oral hälsa hos vuxna individer med utländsk bakgrund: En enkätstudie2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    En stor invandring innebär en ökad påfrestning på tandvården från individer med utländsk bakgrund. Hos individerna med utländsk bakgrund har man funnit en nedsatt oral hälsa. Att undersöka vad individer med utländsk bakgrund vet om orala sjukdomar samt vilka munhygiensvanor de har kan hjälpa till att hitta eventuella riskfaktorer till nedsatt oral hälsa. Detta hjälper tandvården att se inom vilket område man bör informera. och stärka denna grupp för att vid behålla deras orala hälsa. Syfte: Att undersöka munhygiensvanor och kunskaper kring oral hälsa hos vuxna individer med utländsk bakgrund. Frågeställning: Finns det någon skillnad mellan hur ofta män och kvinnor med borstar? Metod: Kvantitativ studie. Empirisk enkätstudie. Enkäten omfattar frågor om munhygienvanor, kunskap om karies och kunskap om parodontit. Urvalet bestod av vuxna män och kvinnor som har en utländsk bakgrund och är över 18 års ålder. Med utländsk bakgrund menas att individerna är födda utomlands och har utländska föräldrar. Studiedeltagarna befann sig på en SFI skola i Mellansverige. Resultat: Antal studiedeltagare som deltog i studien var 78, (n=36 män), (n=29 kvinnor), (n=13 som inte angav kön). Majoriteten av studiedeltagarna visade sig ha goda vanor med antalet gånger de borstar tänderna per dag, hur ofta de använder fluor och användning av orala munhygiensprodukter utöver tandborste. Studien visar även att en mindre del av studiedeltagarna känner de största riskfaktorerna för att få orala sjukdomar. Konklusion: Individer med utländsk bakgrund har goda munhygiensvanor men saknar till viss del kunskap kring orsaken till varför orala sjukdomar som karies och parodontit uppstår.

  • 196.
    Alvarsson, Kristoffer
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Ombyggnation av en svetscell: Utformning av inmatningssystemet2015Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This report deals with a project that´s been initiated on the behalf of Morgan Sahlin at Wermland Mechanics AB in Töcksfors and is about to look over and develop a input system for a welding cell. The project is done in the course Degree of Bachelor of Science in Innovation and Design Engineering, MSGC12 at Karlstad University and comprises 22,5 credits.

    Today the company has received a shelf in the production where one of the steps is to apply a reinforcement by welding. At their disposal, they have a welding cell that today is just standing still, taking up space and costs money. The welding cell has previously been semi-automatic but the company now wish to rebuild it so it instead becomes fully automatic. The goal is to develop a concept that suits the company's operations and that at the end of the project gaze upon a functioning fully automatic welding cell.

    The project follows a project model based on the product development process with the phases pilot study, concept generation, concept selection, concept description, layout and detail design. Each phase is supplemented with specially selected design tools. During the process analyzes, observations, interviews and site visits has also been carried out.

    After the pilot study that was based on observations, analysis and gathering of information, a specification took form where the requirements and requests, of what the final product is expected to achieve, were listed. The specification resulted in the project´s first problem: "How should a feed mechanism to an automated welding cell be designed that allow room for shelves and reinforcements, with focus on the user-friendliness?". This problem was the foundation of the upcoming concept generation and the specification became the basis of the choice of concept.

    The process resulted in two concepts that were presented to the client and which corresponded to the established definition of the problem. Both concepts are based on exploiting how the details arrives and means that they are entered directly into the welding cell on the pallets. The concepts differ in how the shelves are stacked on the pallets, one comprises a solution where the shelves are laying down while in the other one they are standing up. The solution suits the company well and can be adapted to most of the operations in their production.

  • 197.
    Alvinius, Aida
    et al.
    Försvarshögskolan.
    Wilde-Larsson, Bodil
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Larsson, Gerry
    Försvarshögskolan.
    Managing boundaries in integrated care: A qualitative study of collaboration between municipalities and county councils in Sweden2016In: International Journal of Organization Theory and Behavior, ISSN 1093-4537, E-ISSN 1532-4273, Vol. 19, no 2, p. 139-165Article in journal (Refereed)
  • 198.
    Amir, Mustafa
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Skillnaden i förskrivning av de monoklonala antikropparna Rituximab (Mabthera) och Trastuzumab (Herceptin) mellan 2000-2016 i Sverige: En retrospektiv register- och jämförelse studie mellan alla sjukvårdsregioner2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 199.
    Amruth, C.
    et al.
    Lodz Univ Technol, Poland..
    Luszczynska, Beata
    Lodz Univ Technol, , Poland..
    Szymanski, Marek Zdzislaw
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013). Örebro University, Sweden.
    Ulanski, Jacek
    Lodz Univ Technol, Poland..
    Albrecht, Ken
    Tokyo Inst Technol, Japan; Kyushu University, Japan.
    Yamamoto, Kimihisa
    Tokyo Inst Technol,Japan.
    Inkjet printing of thermally activated delayed fluorescence (TADF) dendrimer for OLEDs applications2019In: Organic electronics, ISSN 1566-1199, E-ISSN 1878-5530, Vol. 74, p. 218-227Article in journal (Refereed)
    Abstract [en]

    This study presents the inkjet printing of a novel OLED device with fully solution-processed organic layers that employ TADF material as an emitting layer. The ink was formulated using new TADF material, triazine core carbazole dendrimers with tert-butyl group at the periphery (tBuG2TAZ), dissolved in a mixture of two non-chlorinated solvents. The influence of the print resolution and the substrate temperature on morphology of the printed films was studied and optimized in ambient conditions. The optimized TADF dendrimer layer was then incorporated in the OLEDs as the emitting layer. The best-printed OLEDs exhibited a maximum current efficiency of 18 cd/A and maximum luminance of 6900 cd/m(2). Such values are comparable to the values obtained in spin coated devices made of the same TADF dendrimer. Further, the mobility of charge carriers extracted from transient electroluminescence measurements of printed OLEDs, when compared to reference OLEDs made by spin coating technique, showed similar values. Finally, we have demonstrated the possibility of patterning of emission the area of complex shapes merely by selectively printing the emission layer. These results demonstrate the potential application of the new dendrimer TADF emitters for the fabrication of efficient OLEDs by an inkjet printing technique.

  • 200.
    Amruth, C.
    et al.
    Lodz University of Technology, Poland.
    Szymanski, Marek Zdzislaw
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013). Örebro University.
    Luszczynska, Beata
    Lodz University of Technology, Poland.
    Ulanski, Jacek
    Lodz University of Technology, Poland.
    Inkjet printing of super yellow: Ink formulation, film optimization, OLEDs fabrication, and transient electroluminescence2019In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, p. 1-10, article id 8493Article in journal (Refereed)
    Abstract [en]

    Inkjet printing technique allows manufacturing low cost organic light emitting diodes (OLEDs) in ambient conditions. The above approach enables upscaling of the OLEDs fabrication process which, as a result, would become faster than conventionally used vacuum based processing techniques. In this work, we use the inkjet printing technique to investigate the formation of thin active layers of well-known light emitting polymer material: Super Yellow (poly(para-phenylene vinylene) copolymer). We develop the formulation of Super Yellow ink, containing non-chlorinated solvents and allowing stable jetting. Optimization of ink composition and printing resolution were performed, until good quality films suitable for OLEDs were obtained. Fabricated OLEDs have shown a remarkable characteristics of performance, similar to the OLEDs fabricated by means of spin coating technique. We checked that, the values of mobility of the charge carriers in the printed films, measured by transient electroluminescence, are similar to the values of mobility measured in spin coated films. Our contribution provides a complete framework for inkjet printing of high quality Super Yellow films for OLEDs. The description of this method can be used to obtain efficient printed OLEDs both in academic and in industrial settings.

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