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• 701.
Karlstad University, Division for Information Technology.
TCP in Wireless Networks: Challenges, Optimizations and Evaluations2005Licentiate thesis, comprehensive summary (Other academic)

This thesis presents research on transport layer behavior in wireless networks. As the Internet is expanding its reach to include mobile devices, it has become apparent that some of the original design assumptions for the dominant transport protocol, TCP, are approaching their limits. A key feature of TCP is the congestion control algorithm, constructed with the assumption that packet loss is normally very low, and that packet loss therefore is a sign of network congestion. This holds true for wired networks, but for mobile wireless networks non-congestion related packet loss may appear. The varying signal power inherent with mobility and handover between base-stations are two example causes of such packet loss. This thesis provides an overview of the challenges for TCP in wireless networks together with a compilation of a number of suggested TCP optimizations for these environments. A TCP modification called TCP-L is proposed. It allows an application to increase its performance, in environments where residual bit errors normally give a degraded throughput, by making a reliability tradeoff. The performance of TCP-L is experimentally evaluated with an implementation in the Linux kernel. The transport layer performance in a 4G scenario is also experimentally investigated, focusing on the impact of the link layer design and its parameterization. Further, for emulation-based protocol evaluations, controlled packet loss and bit error generation is shown to be an important aspect.

• 702. Alfredsson, Stefan
TCP Lite - a bit error transparent modification of TCP2001Independent thesis Advanced level (degree of Master (One Year))Student thesis
• 703.
Karlstad University, Division for Information Technology.
Karlstad University, Division for Information Technology.
Bit Error Tolerant Multimedia Transport2004In: Perspectives on Multimedia: Communication, Media and Information Technology, Chichester: John Wiley & Sons, 2004, p. 175-191Chapter in book (Other academic)
• 704.
Karlstad University, Division for Information Technology.
Karlstad University, Division for Information Technology.
TCP-L: Allowing Bit Errors in Wireless TCP2003In: Proceedings of the 12th IST Summit on Mobile and Wireless Communications: Enabling a Pervasive Wireless World / [ed] Atílio Gameiro, Institute for Operations Research and the Management Sciences (INFORMS), 2003, p. 149-154Conference paper (Refereed)

This paper presents a technique to improve the performance of TCP and the utilization of wireless networks.Wireless links exhibit high rates of bit errors, compared to communication over wireline or fiber. Since TCP cannotseparate packet losses due to bit errors versus congestion,all losses are treated as signs of congestion and congestionavoidance is initiated. This paper explores the possibility of accepting TCP packets with an erroneous checksum, toimprove network performance for those applications that can tolerate bit errors. Since errors may be in the TCP header aswell as the payload, the possibility of recovering the headeris discussed. An algorithm for this recovery is also presented.Experiments with an implementation have been performed,which show that large improvements in throughput can beachieved, depending on link and error characteristics.

• 705.
Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Division for Information Technology.
Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Division for Information Technology. Signaler och System, Uppsala universitet.
A 4G Link Level Emulator for Transport Protocol Evaluation2004In: Proceedings of The Second Swedish National Computer Networking Workshop (SNCNW), 2004, p. 19-23Conference paper (Refereed)

• 706.
Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Signaler och System, Uppsala universitet.
Cross-layer analysis of TCP performance in a 4G system2007In: Proceedings of the 15th International Conference on Software, Telecommunications and Computer Networks, IEEE Computer Society, 2007Conference paper (Refereed)

This paper presents results from an experimental study of TCP in a wireless 4G evaluation system. Test-bed results on transport layer performance are presented and analyzed in relation to several link layer aspects. The aspects investigated are the impact of channel prediction errors, channel scheduling, delay, and adaptive modulation switch level, on TCP performance. The paper contributes a cross-layer analysis of the interaction between symbol modulation levels, different scheduling strategies, channel prediction errors and the resulting frame retransmissions effect on TCP. The paper also shows that highly persistent ARQ with fast link retransmissions do not interact negatively with the TCP retransmission timer even for short round trip delays.

• 707.
Karlstad University, Division for Information Technology. Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Division for Information Technology. Signaler och System, Uppsala universitet.
Emulation and Validation of a 4G System Proposal2005In: Proceedings of RadioVetenskap och Kommunikation 2005: Volume II, 2005, p. 357-362Conference paper (Refereed)

• 708.
Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Signaler och System, Uppsala universitet.
Impact of 4G Wireless Link Configurations on VoIP Network Performance2008In: Proceedings of the 2008 IEEE International Symposium on Wireless Communication Systems, IEEE Communications Society, 2008, p. 708-712Conference paper (Refereed)

The performance of applications in wireless networks is partly dependent upon the link configuration. Link characteristics varies with frame retransmission persistency, link frame retransmission delay, adaptive modulation strategies, coding, and more. The link configuration and channel conditions can lead to packet loss, delay and delay variations, which impact different applications in different ways. A bulk transfer application may tolerate delays to a large extent, while packet loss is undesirable. On the other hand, real-time interactive applications are sensitive to delay and delay variations, but may tolerate packet loss to a certain extent. This paper contributes a study of the effect of link frame retransmission persistency and delay on packet loss and latency for real-time interactive applications. The results indicate that a reliable retransmission mechanism with fast link retransmissions in the range of 2-8 ms is sufficient to provide an upper delay bound of 50 ms over the wireless link, which is well within the delay budget of voice over IP applications.

• 709.
Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Signaler och System, Uppsala universitet.
Transport Protocol Performance over 4G Links: Emulation Methodology and Results2006In: Proceedings of the International Symposium on Wireless Communication Systems (ISWCS), IEEE Computer Society, 2006, p. 327-332Conference paper (Refereed)

• 710.
Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
Politecnico di Bari, Italy. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science. Ecole superieure d'Electricite, France; Politecnico di Bari, Italy. Politecnico di Bari, Italy.
Impact of TCP Congestion Control on Bufferbloat in Cellular Networks2013In: Proceedings of the 14th IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks (WoWMoM 2013) / [ed] Angelos Lazaris, Balaji Rengarajan, IEEE Press, 2013Conference paper (Refereed)

The existence of excessively large and too filled network buffers, known as bufferbloat, has recently gained attention as a major performance problem for delay-sensitive applications. One important network scenario where bufferbloat may occur is cellular networks.

This paper investigates the interaction between TCP congestion control and buffering in cellular networks. Extensive measurements have been performed in commercial 3G, 3.5G and 4G cellular networks, with a mix of long and short TCP flows using the CUBIC, NewReno and Westwood+ congestion control algorithms. The results show that the completion times of short flows increase significantly when concurrent long flow traffic is introduced. This is caused by increased buffer occupancy from the long flows. In addition, for 3G and 3.5G the completion times are shown to depend significantly on the congestion control algorithms used for the background flows, with CUBIC leading to significantly larger completion times.

• 711.
Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
Politecnico di Bari, Italy. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science. Ecole superieure d'Electricite, France; Politecnico di Bari, Italy. Politecnico di Bari, Italy.
Observations of Bufferbloat in Swedish Cellular Networks2013In: Proceedings of the 9th Swedish National Computer Networking Workshop (SNCNW 2013) / [ed] Bengt Ahlgren, 2013Conference paper (Refereed)
• 712.
Karlstad University, Faculty of Health, Science and Technology (starting 2013).
Konceptutveckling av transportlösning för kaffeutrustning till event2016Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis

This thesis is done during the spring semester 2016 for the Bachelor of Science in Innovation and Design programme at Karlstad University. The mission of the thesis was provided by the company 3TEMP AB in Arvika.

In order to serve large quantities of coffee at big events, festivals and fairs a powerful coffee machine is required. Due to its size the machine is difficult handle during transport. This project is about finding a solution that makes the transport of the coffee machine and its related equipment safer and easier to handle during transportation between events.

The goal of the project was to find a possible solution that makes the transportation of the equipment more efficient and ergonomic. In order to find as many ideas as possible the design process has been used. This includes a research followed by an ideation, concept development and concept evaluation. The project ended with one concept presented in the form of a layout design in CAD together with assembly drawings, sketches and a model.

In this project interviews and observations has been done together with the people who transport coffee equipment on a daily basis. The results of the observations were later compared with the recommended lifting weight for manual lifting tasks using NOISH lifting equation. In the event business different types of vehicles are used to transport equipment at the event areas. Everything from ATVs and snowmobiles to tractors and caterpillar vehicles are used. In the project there has been a search for a common denominator between those vehicles.

During the project benchmarking of similar products has also been done to find inspiration for new ideas. To further evaluate the concepts an examination of laws and regulations for transportation of equipment in traffic and off-road has been done.

The equipment also has to withstand long distance transport by rail, road, sea and air. To meet these requirements interviews were made with the company MariTerm AB who works with educating in cargo securing of goods for worldwide shipment.

• 713. Alfredsson, Örjan
Svenskt utvecklingssamarbete med Baltikum2001Independent thesis Basic level (degree of Bachelor)Student thesis
• 714.
Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Language, Literature and Intercultural Studies.
Mobbning i litteraturen - då och nu: Skillnader och likheter i beskrivningen av mobbning idag och för 60 år sedan2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis

Abstract

This essay is a comparative study of two youth novels with bullying as a motif. The novels are Vi kallar honom Anna by Peter Pohl and Gilla Hata Horan by Johanna Nilsson. Bullying at school is an ever present problem for students, teachers, parents and school management. The society is obliged to provide a safe and equal environment where every student is included. The school system of today take actions to prevent bullying. I believe literature could play a part in that work. The purpose of the essay is to examine similarities and differences between the texts in how bullying is described 60 years ago, and the bullying that exists today and often takes place on the Internet. I also plan to use the result in literature classes. I have in my analysis used a comparative method, and biografic science where focus lies on what the author wants to say with the text.

My analysis shows that the texts displays many situations that relates to science. There are many similarities and differences between the texts, but the biggest difference is the description of how teachers and management looked at bullying in the 1950s, compared to today. Another difference is the description of how bullying today takes place around the clock, compared with how bullying mainly took place during school time 50 years ago, differences that clearly is stated in the novels. Back in the day you knew who the persons that performed bullying was. Today you can be anonymous, which makes it hard to know who is behind it. Both authors have their own experiences from bullying with a time difference of 40-50 years. Despite the time gap bullying is described with essentially the same universal components in cause and effect.

Keywords: Bullying, study of motifs, comparative, intertextuality

• 715.
Karlstad University, Faculty of Arts and Education.
Tappar ungdomarna standardspråket om chatt/ungdomsspråket används inom skolan?: En studie av chatt/ungdomsspråkets inverkan på skriftspråket2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
Norsk regionalpolitikk i et europeisk perspektiv - norsk utakt?2003Independent thesis Advanced level (degree of Master (One Year))Student thesis
• 717.
En skärgårdskommun på kryss mot framtiden: Framväxten av ett EU-projekt i Nynäshamns kommun. En fallstudie2013Student paper second term, 5 credits / 7,5 HE creditsStudent thesis
• 718. Algell, Erik
Aktiekursens rörelse runt ex-dagen - en kvantitativ analys på Stockholmsbörsen2004Independent thesis Basic level (degree of Bachelor)Student thesis
• 719. Algell, Erik
Den digitala tvättstugan2007Independent thesis Basic level (professional degree)Student thesis
• 720.
Karlstad University, Faculty of Health, Science and Technology (starting 2013).
Distriktssköterskan och telefonrådgivningen: En litteraturstudie2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis

Introduction : The district nurse makes assessment, refers and provides advice, support and information to the public in telephone consulting. Telephone counseling is a growing part of healthcare and is a complex area of health care, where district nurses encounter many new situations and challenges. District nurses offer self-care to the public in telephone counseling.

Aim: To identify which factors create opportunities and provide limitations, there is a district nurse's task in telephone counseling in primary care.

Method: A systematic literature study with descriptive synthesis based on nine scientific articles published 2008-2018. The articles were searched in databases PubMed and Cinahl. The articles were processed with qualitative content analysis.

Result: Nurses thought it was exhaustive to assess and handle conversations appropriately. Communication skills should be highly developed in the telephone-based meetings. The cognitive fatigue caused the nurse to fail to listen to the caller and led to the nurse asking too few questions. Nurses perceived that computerized decision support was both positive and negative.

Conclusion: Nurses thought the decision support system was complementary support, it was perceived as a valuable source of information. Communication skills are a very important tool in telephone consulting. Cognitive fatigue due to long workouts had a major impact on the nurses' assessment.

• 721.
Karlstad University, Faculty of Technology and Science, Avdelningen för matematik.
Embedding Theorems for Mixed Norm Spaces and Applications2010Doctoral thesis, monograph (Other academic)

This thesis is devoted to the study of mixed norm spaces that arise in connection with embeddings of Sobolev and Besov type spaces. We study different structural, integrability, and smoothness properties of functions satisfying certain mixed norm conditions. Conditions of this type are determined by the behaviour of linear sections of functions. The work in this direction originates in a paper due to Gagliardo (1958), and was further developed by Fournier (1988), by Blei and Fournier (1989), and by Kolyada (2005).

Here we continue these studies. We obtain some refinements of known embeddings for certain mixed norm spaces introduced by Gagliardo, and we study general properties of these spaces. In connection with these results, we consider a scale of intermediate mixed norm spaces, and prove intrinsic embeddings in this scale.

We also consider more general, fully anisotropic, mixed norm spaces. Our main theorem states an embedding of these spaces to Lorentz spaces. Applying this result, we obtain sharp embedding theorems for anisotropic Sobolev-Besov spaces, and anisotropic fractional Sobolev spaces. The methods used are based on non-increasing rearrangements, and on estimates of sections of functions and sections of sets. We also study limiting relations between embeddings of spaces of different type. More exactly, mixed norm estimates enable us to get embedding constants with sharp asymptotic behaviour. This gives an extension of the results obtained for isotropic Besov spaces by Bourgain, Brezis, and Mironescu, and for anisotropic Besov spaces by Kolyada.

We study also some basic properties (in particular the approximation properties) of special weak type spaces that play an important role in the construction of mixed norm spaces, and in the description of Sobolev type embeddings.

In the last chapter, we study mixed norm spaces consisting of functions that have smooth sections. We prove embeddings of these spaces to Lorentz spaces. From this result, known properties of Sobolev-Liouville spaces follow.

• 722.
Karlstad University, Faculty of Technology and Science, Avdelningen för matematik.
Embedding Theorems for Mixed Norm Spaces and Applications2008Licentiate thesis, monograph (Other scientific)

This thesis is devoted to the study of mixed norm spaces that arise in connection with embeddings of Sobolev and Besov type spaces. The work in this direction originates in a paper due to Gagliardo (1958), and was continued by Fournier (1988) and by Kolyada (2005).

We consider fully anisotropic mixed norm spaces. Our main theorem states an embedding of these spaces into Lorentz spaces. Applying this result, we obtain sharp embedding theorems for anisotropic fractional Sobolev spaces and anisotropic Sobolev-Besov spaces. The methods used are based on non-increasing rearrangements and on estimates of sections of functions and sections of sets. We also study limiting relations between embeddings of spaces of different type. More exactly, mixed norm estimates enable us to get embedding constants with sharp asymptotic behaviour. This gives an extension of the results obtained for isotropic Besov spaces $B_p^\alpha$ by Bourgain, Brezis, and Mironescu, and for Besov spaces $B^{\alpha_1,\dots,\alpha_n}_p$ by Kolyada.

We study also some basic properties (in particular the approximation properties) of special weak type spaces that play an important role in the construction of mixed norm spaces and in the description of Sobolev type embeddings.

• 723.
Karlstad University, Faculty of Technology and Science, Department of Mathematics.
Karlstad University, Faculty of Technology and Science, Department of Mathematics.
On Fournier-Gagliardo mixed norm spaces2011In: Annales Academiae Scientiarum Fennicae Mathematica, ISSN 1239-629X, Vol. 36, p. 493-508Article in journal (Refereed)

We study mixed norm spaces

V (Rn)

that arise in connection with embeddings of

Sobolev spaces

W

1

1

(Rn). We prove embeddings of V (Rn)

into Lorentz type spaces defined in terms

of iterative rearrangements. Basing on these results, we introduce the scale of mixed norm spaces

V

p

(Rn). We prove that V ½ V p

and we discuss some questions related to this embedding.

• 724.
Svenska som andraspråk på grundskolan: Ett ämne som kan integreras i svenskämnet?2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
• 725. Algotson, Martin
Diagnosen Aspergers syndrom - två Asperger-enheter i Karlskoga2007Independent thesis Basic level (degree of Bachelor)Student thesis
• 726. Algotsson, Malin
Elever tycker om feedback2006Independent thesis Basic level (professional degree)Student thesis

Syftet med det här arbetet är att undersöka vad elever tycker om skriftlig feedback i språkundervisningen och vilken typ av feedback de vill ha på sina skriftliga arbeten. Med en enkätundersökning och fyra intervjuer i år nio utforskades elevers synpunkter om språklärares feedback. Eleverna visade sig ha en överlag positiv inställning till feedback. Majoriteten föredrar tydliga kommentarer med vad som är bra respektive mindre bra samt förslag på ändring framför enbart rättande ”bockar” och ”R”. Det framkom att eleverna betraktar fel som en naturlig del i språkinlärningen som de är angelägna om att bli informerade om. Nyckelord är skriftlig feedback, skriftliga arbeten, språkundervisning, elevperspektiv.

• 727.
Karlstad University, Faculty of Social and Life Sciences.
Om barn och sorg - hur kan vi vuxna se, förstå och hjälpa?: About children and grief - How can we as adultes see, understand and help?2008Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis

Abstract

To become a teacher it is important to have some knowledge about children’s grief. It is likely that you at least once will come in contact with a pupil who has lost a parent or a sibling. Than it’s important to know how we as adults/teachers can handle this problem. In this paper I have interviewed four different teachers who work at four different schools and they all have 25-30 years experience of their profession. I have asked them about children and grief. How can we as adults see, understand and help? How dose the school handle this situation?

Do they follow a special crises plan? And how were the reactions from the pupils in crises?

The literature shows that children’s grief can look different and it’s important too realise that.

My main conclusion is that its important too talk about death even with small children. Every school is helped with having a crises plan, the teacher has an important role for child who has lost a relative. Sometimes the school is the only place were there are no hysterical, crying people and were everything is as it used to be.

Keywords: reactions of grief, crisis plan in school, grief, dealing with grief in school

• 728.
Univ Lisbon, Ctr Math Anal Geometry & Dynam Syst, Inst Super Tecn, Av Rovisco Pais, P-1049001 Lisbon, Portugal..
Univ Lisbon, Ctr Multidisciplinar Astrofis CENTRA, Inst Super Tecn, Av Rovisco Pais, P-1049001 Lisbon, Portugal.. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
On dynamical systems approaches and methods in f (R) cosmology2016In: Journal of Cosmology and Astroparticle Physics, ISSN 1475-7516, E-ISSN 1475-7516, no 8, article id 064Article in journal (Refereed)

We discuss dynamical systems approaches and methods applied to flat Robertson Walker models in f(R)-gravity. We argue that a complete description of the solution space of a model requires a global state space analysis that motivates globally covering state space adapted variables. This is shown explicitly by an illustrative example, f(R) = R + alpha R-2, alpha > 0, for which we introduce new regular dynamical systems on global compactly extended state spaces for the Jordan and Einstein frames. This example also allows us to illustrate several local and global dynamical systems techniques involving, e.g., blow ups of nilpotent fixed points, center manifold analysis, averaging, and use of monotone functions. As a result of applying dynamical systems methods to globally state space adapted dynamical systems formulations, we obtain pictures of the entire solution spaces in both the Jordan and the Einstein frames. This shows, e.g., that due to the domain of the conformal transformation between the Jordan and Einstein frames, not all the solutions in the Jordan frame are completely contained in the Einstein frame. We also make comparisons with previous dynamical systems approaches to f (R) cosmology and discuss their advantages and disadvantages.

• 729.
University of Lisbon, Portugal.
Free University Berlin, Germany. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
Global dynamics and asymptotics for monomial scalar field potentials and perfect fluids2015In: Classical and quantum gravity, ISSN 0264-9381, E-ISSN 1361-6382, Vol. 32, no 14, article id 145005Article in journal (Refereed)

We consider a minimally coupled scalar field with a monomial potential and a perfect fluid in flat Friedmann-Lemaitre-Robertson-Walker cosmology. We apply local and global dynamical systems techniques to a new three-dimensional dynamical systems reformulation of the field equations on a compact state space. This leads to a visual global description of the solution space and asymptotic behavior. At late times we employ averaging techniques to prove statements about how the relationship between the equation of state of the fluid and the monomial exponent of the scalar field affects asymptotic source dominance and asymptotic manifest self-similarity breaking. We also situate the ’attractor’ solution in the three-dimensional state space and show that it corresponds to the one-dimensional unstable center manifold of a de Sitter fixed point, located on an unphysical boundary associated with the dynamics at early times. By deriving a center manifold expansion we obtain approximate expressions for the attractor solution. We subsequently improve the accuracy and range of the approximation by means of Pade approximants and compare with the slow-roll approximation.

• 730.
Technical University of Lisbon, Portugal.
Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
Global dynamics and inflationary center manifold and slow-roll approximants2015In: Journal of Mathematical Physics, ISSN 0022-2488, E-ISSN 1089-7658, Vol. 56, no 1, article id 012502Article in journal (Refereed)

We consider the familiar problem of a minimally coupled scalar field with quadratic potential in flat Friedmann-Lemaître-Robertson-Walker cosmology to illustrate a number of techniques and tools, which can be applied to a wide range of scalar field potentials and problems in, e.g., modified gravity. We present a global and regular dynamical systems description that yields a global understanding of the solution space, including asymptotic features. We introduce dynamical systems techniques such as center manifold expansions and use Padé approximants to obtain improved approximations for the “attractor solution” at early times. We also show that future asymptotic behavior is associated with a limit cycle, which shows that manifest self-similarity is asymptotically broken toward the future and gives approximate expressions for this behavior. We then combine these results to obtain global approximations for the attractor solution, which, e.g., might be used in the context of global measures. In addition, we elucidate the connection between slow-roll based approximations and the attractor solution, and compare these approximations with the center manifold based approximants.

• 731.
Center for Mathematical Analysis, Geometry and Dynamical Systems, Instituto Superior Técnico, Universidade de Lisboa, Portugal.
Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
Inflationary alpha-attractor cosmology: A global dynamical systems perspective2017In: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 95, no 8, article id 083517Article in journal (Refereed)

We study flat Friedmann-Lemaitre-Robertson-Walker alpha-attractor E- and T-models by introducing a dynamical systems framework that yields regularized unconstrained field equations on two-dimensional compact state spaces. This results in both illustrative figures and a complete description of the entire solution spaces of these models, including asymptotics. In particular, it is shown that observational viability, which requires a sufficient number of e-folds, is associated with a particular solution given by a one-dimensional center manifold of a past asymptotic de Sitter state, where the center manifold structure also explains why nearby solutions are attracted to this "inflationary attractor solution." A center manifold expansion yields a description of the inflationary regime with arbitrary analytic accuracy, where the slow-roll approximation asymptotically describes the tangency condition of the center manifold at the asymptotic de Sitter state.

• 732.
Univ Lisbon, Inst Super Tecn, Ctr Math Anal Geometry & Dynam Syst, P-1049001 Lisbon, Portugal..
Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
Scalar field deformations of Lambda CDM cosmology2015In: Physical Review D, ISSN 1550-7998, E-ISSN 1550-2368, Vol. 92, no 10, article id 103502Article in journal (Refereed)

This paper treats nonrelativistic matter and a scalar field phi with a monotonically decreasing potential minimally coupled to gravity in flat Friedmann-Lemaitre-Robertson-Walker cosmology. The field equations are reformulated as a three-dimensional dynamical system on an extended compact state space, complemented with cosmographic diagrams. A dynamical systems analysis provides global dynamical results describing possible asymptotic behavior. It is shown that one should impose global and asymptotic bounds on lambda = -V-1 dV/d phi to obtain viable cosmological models that continuously deform Lambda CDM cosmology. In particular we introduce a regularized inverse power-law potential as a simple specific example.

• 733. Ali, A
Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
Growing window recursive quadratic optimization with variable regularization2010Conference paper (Refereed)
• 734.
Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
Predicted Speed Control based on Fuzzy Logic for Belt Conveyors: Fuzzy Logic Control for Belt Conveyors2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis

• 735.
Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA..
Univ Kentucky, Dept Mech Engn, 151 Ralph G Anderson Bldg, Lexington, KY 40507 USA.. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics. Univ Michigan, Dept Aerosp Engn, Ann Arbor, MI 48109 USA..
On the stability and convergence of a sliding-window variable-regularization recursive-least-squares algorithm2016In: International journal of adaptive control and signal processing (Print), ISSN 0890-6327, E-ISSN 1099-1115, Vol. 30, no 5, p. 715-735Article in journal (Refereed)

A sliding-window variable-regularization recursive-least-squares algorithm is derived, and its convergence properties, computational complexity, and numerical stability are analyzed. The algorithm operates on a finite data window and allows for time-varying regularization in the weighting and the difference between estimates. Numerical examples are provided to compare the performance of this technique with the least mean squares and affine projection algorithms. Copyright (c) 2015 John Wiley & Sons, Ltd.

• 736. Ali Irfan, Mehmood
Social Media Marketing (Dell): How Dell is using social marketing media tool to promote its image in Sweden2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
• 737.
Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Geography, Media and Communication.
Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Geography, Media and Communication.
Varför varierar skolresultaten bland eleverna i Göteborg beroende på var de bor?: Skolsegregation i Göteborg2017Student paper second term, 5 credits / 7,5 HE creditsStudent thesis
Hot wear of new tool steel development for aluminium extrusion dies2005Independent thesis Advanced level (degree of Master (One Year))Student thesis

Tools for aluminium extrusion have limited life due to wear of the extrusion die. The extrusion process takes place at elevated temperature 550-600°C. This process is defined as the process of transforming a metal billet into long sections for example profiles, beams or rods. One heated round aluminium bar is pressed through a die and out comes an extruded profile. For higher wear resistance and longer life the bearing surface is often surface treated by nitriding. Four different tool steel grades were investigated i.e. new tool steel developed for aluminium extrusion dies. These tool steel grades were surface treated by the gas nitrocarburizing processes and one untreated tool steel for reference. The wear test used is a block-on-cylinder set up at temperature 550°C. The aluminum alloy AA 6063 is used as a counter material. The tool steel block is pressed against a rotating aluminium cylinder. The worn volume was measured by OP (Optical Profilometry). The properties of the new tool steel were investigated by LOM, their microstructure before and after surface treatment, and compared with the reference material H13.Four different types of tool steels were studied by SEM to characterize the wear pattern and to identify the wear mechanisms. It is concluded that for the nitrocarburizing treatment, chemical wear is a common wear mechanism due to the formation of intermetallic compounds. Delamination wear also observed on the worn surface. The alloy Unimax 1593A and ExW 2090A have good properties for aluminium extrusion dies due to higher hardness of the diffusion zone and lower wear rate than the other experimental tool steel.

• 739.
Customer-support Service - The Role in Telecom-Customer Relationships: A Qualitative Study of Telecom Sector2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

Abstract

From the past few years in Sweden telecommunication business has been altered. Earlier when telecom industry was dominant in the market but now it is transformed in to more competitive market with further competitors and provides additional services. In Sweden TeliaSonera is one of the leading and superior telecommunication providers. Currently TeliaSonera is merged among two large companies such as Telia which was one of the outstanding telecommunication companies in all over Sweden and Sonera is the finish counterpart of Telia. TeliaSonera presently facilitate their customers as well as business customers by proving different communication services such as mobile telephony, mobile broadband, Broadband, fix telephony connection and TV.

Regarding Customer support service the purpose of this study is to investigate the relationship among customers and telecommunication service providers, and in this study we emphasize on customer-support service concerning “The Role in Customer Relationships”. Our consideration is to find out the better relationship among telecommunication service providers and their customers. Additionally the role of Telia shop is also studied by taking interviews with Telia customer representative office (CRO) and Telia top management.

Furthermore from theoretical perspective the research has been conducted through current literatures such as customer support service, relationship marketing, dominant logic, customer loyalty, complaining behavior and trigger model. Approximately all of the literatures are specify from customer viewpoint business processes intended for long lasting relationship. We have sufficient information concerning that how to get better and stand long lasting relationship with the customers in future.

For the fruitful outcome we conducted this research by exploratory research method and also conducted interview with the help of open ended questionnaire and our target group was TeliasSonera Top management in Stockholm, manager of TeliaSonera shop in Karlstad city and also from 12 students of Karlstad University. The reason behind this was to know the role of TeliaSonera towards customer-support service as well as their customer experience and perception. Finally in the end we come up with the conclusion by the help of gathering qualitative information that the effective customer support-service can lead to long lasting relationship among customers and telecom sectors. Furthermore we also came to know in the end that superior quality customer support service assist to create more customers loyalty. That means customer-support service play one of the significant role between telecommunication service provider and customers.

• 740.
Karlstad University, Faculty of Social and Life Sciences.
Karlstad University, Faculty of Social and Life Sciences.
Sjuksköterskans upplevelser av att arbeta med patientfokuserad vård: en litteraturstudie2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
• 741.
Karlstad University, Faculty of Economic Sciences, Communication and IT.
Karlstad University, Faculty of Economic Sciences, Communication and IT.
﻿Halal Food: Thai Halal Food Products and International Market2010Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis

This paper aims to examine salient issues in the Halal food business with special focus on entering Thai Halal food products into international market. Market screening plays an important role in entering new market or setting up the business in the foreign country. In this paper we have analyzed the importance of Halal Food for the Muslims and explained the growth of Halal food in French markets. The study focuses attention on the identification of key areas in Halal food export and channel strategy. The Thai food industry is amongst dynamic and diverse and we investigated the entering process into the new market. Thai food product is selected to compare and find the competitive advantage.

• 742.
Brunel University, London, UK.
University of Limerick, Ireland. Red Orkid Limited, Dublin, Ireland. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). University of Limerick, Ireland.
Architecture consistency: State of the practice, challenges and requirements2018In: Journal of Empirical Software Engineering, ISSN 1382-3256, E-ISSN 1573-7616, Vol. 23, no 1, p. 224-258Article in journal (Refereed)

Architecture Consistency (AC) aims to align implemented systems with their intended architectures. Several AC approaches and tools have been proposed and empirically evaluated, suggesting favourable results. In this paper, we empirically examine the state of practice with respect to Architecture Consistency, through interviews with nineteen experienced software engineers. Our goal is to identify 1) any practises that the companies these architects work for, currently undertake to achieve AC; 2) any barriers to undertaking explicit AC approaches in these companies; 3) software development situations where practitioners perceive AC approaches would be useful, and 4) AC tool needs, as perceived by practitioners. We also assess current commercial AC tool offerings in terms of these perceived needs. The study reveals that many practitioners apply informal AC approaches as there are barriers for adopting more formal and explicit approaches. These barriers are: 1) Difficulty in quantifying architectural inconsistency effects, and thus justifying the allocation of resources to fix them to senior management, 2) The near invisibility of architectural inconsistency to customers, 3) Practitioners’ reluctance towards fixing architectural inconsistencies, and 4) Practitioners perception that huge effort is required to map the system to the architecture when using more formal AC approaches and tools. Practitioners still believe that AC would be useful in supporting several of the software development activities such as auditing, evolution and ensuring quality attributes. After reviewing several commercial tools, we posit that AC tool vendors need to work on their ability to support analysis of systems made up of different technologies, that AC tools need to enhance their capabilities with respect to artefacts such as services and meta-data, and to focus more on non-maintainability architectural concerns.

• 743.
Brunel University, London, UK.
University of Limerick, Ireland. Red Orkid Limited, Dublin, Ireland. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). University of Limerick, Ireland.
Architecture consistency: State of the practice, challenges and requirements (vol 23, pg 224, 2018)2018In: Journal of Empirical Software Engineering, ISSN 1382-3256, E-ISSN 1573-7616, Vol. 23, no 3, p. 1868-1869Article in journal (Refereed)
• 744.
Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
Får män dyrare och nyare läkemedel än kvinnor?: En intervjustudie om läkemedelsskillnader mellan män och kvinnor och mellan socioekonomiska grupper i samhället2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
• 745. Ali Yahiya, Tara
Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
Seamless Interworking of WLAN and WMAN Wireless Networks2006Conference paper (Refereed)

Future network environments will be heterogeneous and mobile terminals will have the opportunity to dynamically select among many different access technologies. Therefore, it is important to provide service continuity in case of vertical handovers when terminals change the access technology. Two important wireless access technologies are WLAN (Wireless Local Access Networks) and WMAN (Wireless Metropolitan Access Networks) networks. In this paper, we address several challenges related to a seamless integration of those technologies. We highlight important aspects for designing a WLAN/WMAN interworking architecture and we address important Quality of Service (QoS) issues for such interworked systems like degree of QoS support provided by the technologies, QoS mapping and signalling for vertical handover. By formulating several interworking scenarios, where WLAN users with ongoing voice, video and data sessions hand over to WMAN, we study QoS and performance issues and analyse feasibility of seamless session continuity through simulations

• 746. Aliaar, Mehdi
Analysis of the IT-department of a finacial company2005Independent thesis Advanced level (degree of Master (One Year))Student thesis
• 747.
Revisionspliktens avskaffande: En kvalitativ studie av fyra intressenters remissvar2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

This paper describes and analyzes the four stakeholders' views on the possible risk of increased information asymmetry as a consequence of the abolition of the audit duty for small private limited companies in Sweden. The four stakeholders are the Economic Crimes Bureau, the Tax Agency, the Swedish Competition Authority and the Swedish Bankers' Association.

The object of study in this paper is the four stakeholder consultation response of the audit duty abolition. Their replies are analyzed and interpreted using the stakeholder model, the agent theory, the stewardship theory and the legitimacy theory.

The Swedish Economic Crime Authority and the Swedish Tax Agency, both rejects the legislative amendment. Competition Authority and the Swedish Bankers' Association, however, are both positive to the bill. The explanation for their different positions is that they have different interests in the companies affected.

The consultation of the Swedish Tax Agency and the Swedish Economic Crimes Bureau show that they are concerned that the information asymmetry between them as principal and the companies / agent will increase. The Swedish Competition Authority's consultation response contains no discussion that can be interpreted as a concern for greater information asymmetry. The Swedish Bankers' Association shows no concern for increased information asymmetry since they solve such problems through contractual agreements. The Swedish Bankers' Association is the only one of the four consultative stakeholders that has any discussion reminiscent of the Stewardship theory thought structure, since they by guarantee commitments make the interest of the bank/principal and the steward conflate.

• 748. Alila-Ojala, Helena
Medarbetarens självförtroende och förändringsförmåga påverkar hennes inställning till kompetensutveckling2003Independent thesis Basic level (degree of Bachelor)Student thesis

Dagens samhälle och näringsliv förändras ständigt i en allt mer accelererande takt. Givetvis ställer detta krav på företag och dess medarbetare. Därmed har kompetensutveckling blivit allt viktigare för företagen. Kompetensutveckling kan medföra nya kunskaper och nytt lärande för medarbetaren. Detta i sin tur kan leda till nya arbetsuppgifter inom företaget och ställer krav på medarbetarens vilja att kompetensutveckla sig. Därför är syftet med undersökningen att studera ifall viljan till kompetensutveckling påverkas av hennes förändringsförmåga och självförtroende. Undersökningen genomfördes med hjälp av en enkätförfrågning i ett papperstillverkande företag i Värmland. Urvalet gjordes utifrån bekvämlighetsprincipen där 100 av 180 produktionspersonal valdes till undersökningen, var av 67 deltog. Undersökningsresultatet visar att medarbetarens förmåga att följa med i olika förändringar påverkar hennes inställning till kompetensutveckling. Studien har även kommit fram till att starkt/svagt självförtroendet har en viss påverkan på medarbetarens förändringsförmåga. Dock har vissa reliabilitets- och validitetsbrister påverkat resultatet.

• 749.
Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
Studier av effekter av epigallokatekingallat och extrakt av grönt te och kråkbär på enzymer involverade i prostaglandin bildning i humana monocyter och makrofager2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
• 750. Alipour, Friya
Omvårdnadsinterventioner i form av support till patienter med prostatacancer och deras partner: En litteraturstudie2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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