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  • 301.
    Almang, Jan
    Karlstads universitet, Fakulteten för humaniora och samhällsvetenskap (from 2013), Institutionen för pedagogiska studier (from 2013).
    War, vagueness and hybrid war2019Ingår i: Defence Studies, ISSN 1470-2436, E-ISSN 1743-9698, Vol. 19, nr 2, s. 189-204Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It has frequently been observed in the literature on hybrid wars that there is a grey zone between peace and war, and that hybrid wars are conflicts which are not clear cases of war. In this paper, I attempt to illuminate this grey zone and the concept and nature of war from the philosophical discussions of vagueness and institutional facts. Vague terms are characterized by the fact that there is no non-arbitrary boundary between entities which lie in their extension, and entities which do not lie in their extension. I apply a theory of vagueness to notions such as “war” and “peace” and go on to suggest that the exact boundary for what counts as a war or not is arbitrary. However, the context in which the conflict occurs determines a range of possible locations for this boundary. The most important contextual parameter is in this respect how the parties to the conflict themselves conceptualize the conflict. I suggest that this can in various ways help us understand grey-zone conflicts.

  • 302.
    Almani, T.
    et al.
    UT Austin, Ctr Subsurface Modeling, ICES, Austin, TX 78712 USA.;Saudi Arabian Oil Co, Dhahran, Saudi Arabia..
    Kumar, Kundan
    Univ Bergen, Math Inst, N-5020 Bergen, Norway..
    Dogru, A.
    Saudi Arabian Oil Co, Dhahran, Saudi Arabia..
    Singh, G.
    UT Austin, Ctr Subsurface Modeling, ICES, Austin, TX 78712 USA..
    Wheeler, M. F.
    UT Austin, Ctr Subsurface Modeling, ICES, Austin, TX 78712 USA..
    Convergence analysis of multirate fixed-stress split iterative schemes for coupling flow with geomechanics2016Ingår i: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 311, s. 180-207Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We consider multirate iterative schemes for the Biot system modeling coupled flow and geomechanics in a poro-elastic medium. The multirate iterative 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 adapt the fixed stress split algorithm that decouples the flow and mechanics equations for the multirate case and perform an iteration between the two problems until convergence. We provide a fully discrete scheme that uses Backward Euler time discretization and mixed spaces for flow and conformal Galerkin for mechanics. Our analysis is based on studying the equations satisfied by the difference of iterates and using Banach contraction argument to prove that the corresponding scheme is a fixed point contraction. The analysis provides the value of an adjustable coefficient used in the proposed iterative coupling algorithms. Furthermore, we show that the converged quantities satisfy the variational weak form for the coupled discrete system. (C) 2016 Elsevier B.V. All rights reserved.

  • 303.
    Almani, T.
    et al.
    Austin, USA.
    Kumar, Kundan
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för matematik och datavetenskap (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 medium2019Ingår i: Computers and Mathematics with Applications, ISSN 0898-1221, E-ISSN 1873-7668, Vol. 78, nr 8, s. 2682-2699Artikel i tidskrift (Refereegranskat)
    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.

  • 304.
    Almani, T.
    et al.
    Center for Subsurface Modeling, ICES, UT-Austin, Austin, USA; Saudi Arabian Oil Company (Aramco), Dhahran, Saudi Arabia.
    Kumar, Kundan
    Mathematics Institute, University of Bergen, Bergen, Norway.
    Wheeler, M. F.
    Center for Subsurface Modeling, ICES, UT-Austin, Austin, USA.
    Convergence and error analysis of fully discrete iterative coupling schemes for coupling flow with geomechanics2017Ingår i: Computational Geosciences, ISSN 1420-0597, E-ISSN 1573-1499, Vol. 21, nr 5-6, s. 1157-1172Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we consider an iterative coupling scheme for solving a fully discretized Biot system based on the fixed-stress split coupling algorithm. Specifically, we derive a priori error estimates for quantifying the error between the solution obtained at any iterate and the true solution. Our approach is based on studying the equations satisfied by the difference of iterates and utilizing a Banach contraction argument to show that the corresponding scheme is a fixed point iteration. Obtained contraction results are then used to derive theoretical convergence error estimates for the single rate iterative coupling scheme. We compare our numerical computations against the theoretically derived contraction estimates and show a good agreement with theory.

  • 305.
    Almani, T.
    et al.
    Saudi Arabian Oil Company (Aramco), Saudi Arabia.
    Manea, A.
    Saudi Arabian Oil Company (Aramco), Saudi Arabia.
    Kumar, Kundan
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för matematik och datavetenskap (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 media2019Ingår i: Computational Geosciences, ISSN 1420-0597, E-ISSN 1573-1499Artikel i tidskrift (Refereegranskat)
    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.

  • 306.
    Almasri, Abdullah
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för nationalekonomi och statistik.
    A Approach for Analysing the Fractional Difference Processes2006Konferensbidrag (Refereegranskat)
  • 307.
    Almasri, Abdullah
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för nationalekonomi och statistik.
    Some aspects of wavelet analysis in time series2000Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 308.
    Almasri, Abdullah
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för nationalekonomi och statistik.
    Testing for Periodicity and Trend in Long-Memory Processes2003Doktorsavhandling, monografi (Övrigt vetenskapligt)
  • 309.
    Almasri, Abdullah
    et al.
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för nationalekonomi och statistik.
    Andersson, Eva M
    Barregård, Lars
    A study of residential radon in Sweden using multilevel analysis2008Ingår i: Health Physics Journal, to appear 2008Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A Swedish radon data set, consisting of more than 8000 measurements of residential radon levels in about 50% of the Swedish municipalities were analysed using a multilevel approach.

    The results were compared with those of a single-level analysis. We found that there was a significant variability between municipalities. The point estimates of the population mean radon levels were similar (geometric mean 60 Bq/m3 and arithmetic mean 106 Bq/m3).

    The analysis shows the advantages of multilevel modeling compared with a single-level OLS model.

    A single-level model results in too optimistic standard errors, about 25% of those of the multilevel

    model which can lead to erroneous conclusions.

    In a multilevel model including house type as a fixed effect (single-family house, row house, or apartment in multi-family house), the estimates of the fixed effect of house type were similar for the single-level and the multi-level models

  • 310.
    Almasri, Abdullah
    et al.
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för nationalekonomi och statistik.
    Hussain, S
    Holmquist, B
    Impact of the Periodicity and Trend on the FD Parameter Estimation2007Ingår i: Journal of Statistical Computation and Simulation. 2007, 77, 79-87Artikel i tidskrift (Refereegranskat)
  • 311.
    Almasri, Abdullah
    et al.
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för nationalekonomi och statistik.
    Locking, Håkan
    Shukur, Ghazi
    Testing for climate warming in Sweden during 1850-1999, using wavelets analysis2008Ingår i: Journal of Applied Statistics, 2008, vol. 35, issue 4, pages 431-443Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper describes an alternative approach for testing for the existence of trend among time series. The test method has been constructed using wavelet analysis which has the ability of decomposing a time series into low frequencies (trend) and high-frequency (noise) components. Under the normality assumption, the test is distributed as F. However, using generated empirical critical values, the properties of the test statistic have been investigated under different conditions and different types of wavelet. The Harr wavelet has shown to exhibit the highest power among the other wavelet types. The methodology here has been applied to real temperature data in Sweden for the period 1850-1999. The results indicate a significant increasing trend which agrees with the 'global warming' hypothesis during the last 100 years.

  • 312.
    Almasri, Abdullah
    et al.
    Karlstads universitet, Fakulteten för humaniora och samhällsvetenskap (from 2013), Handelshögskolan (from 2013).
    Mansson, K.
    Gothenburg Univ, Dept Econ & Stat, Gothenburg, Sweden.;Jonkoping Int Business Sch, Dept Econ Finance & Stat, Jonkoping, Sweden..
    Sjolander, P.
    Jonkoping Int Business Sch, Dept Econ Finance & Stat, Jonkoping, Sweden..
    Shukur, G.
    Jonkoping Int Business Sch, Dept Econ Finance & Stat, Jonkoping, Sweden.;Linnaeus Univ, Dept Econ & Stat, Vaxjo, Sweden..
    A wavelet-based panel unit-root test in the presence of an unknown structural break and cross-sectional dependency, with an application of purchasing power parity theory in developing countries2017Ingår i: Applied Economics, ISSN 0003-6846, E-ISSN 1466-4283, Vol. 49, nr 21, s. 2096-2105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article introduces two different non-parametric wavelet-based panel unit-root tests in the presence of unknown structural breaks and cross-sectional dependencies in the data. These tests are compared with a previously suggested non-parametric wavelet test, the parameteric Im-Pesaran and Shin (IPS) test and a Wald type of test. The results from the Monte Carlo simulations clearly show that the new wavelet-ratio tests are superior to the traditional tests both in terms of size and power in panel unit-root tests because of its robustness to cross-section dependency and structural breaks. Based on an empirical Central American panel application, we can, in contrast to previous research (where bias due to structural breaks is simply disregarded), find strong, clear-cut support for purchasing power parity (PPP) in this developing region.

  • 313.
    Almasri, Abdullah
    et al.
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för nationalekonomi och statistik.
    Shukur, G.
    An Illustration of the Causality Relation between Government Spending and Revenue Using Wavelets Analysis on Finish Data2003Ingår i: Journal of Applied Statistics, 2003, 30, 571-584Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Quarterly data for the period 1960:1 to 1997:2, conventional tests, a bootstrap simulation approach and a multivariate Rao's F-test have been used to investigate if the causality between government spending and revenue in Finland was changed at the beginning of 1990 due to future plans to create the European Monetary Union (EMU). The results indicate that during the period before 1990, the government revenue Granger-caused spending, while the opposite happened after 1990, which agrees better with Barro's tax smoothing hypothesis. However, when using monthly data instead of quarterly data for almost the same sample period, totally different results have been noted. The general conclusion is that the relationship between spending and revenue in Finland is still not completely understood. The ambiguity of these results may well be due to the fact that there are several time scales involved in the relationship, and that the conventional analyses may be inadequate to separate out the time scale structured relationships between these variables. Therefore, to investigate empirically the relation between these variables we attempt to use the wavelets analysis that enables us to separate out different time scales of variation in the data. We find that time scale decomposition is important for analysing these economic variables.

  • 314.
    Almasri, Abdullah
    et al.
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för nationalekonomi och statistik.
    Shukur, G
    Testing the Causal Relation between Sunspots and Temperature Using Wavelets Analysis2005Ingår i: Journal of Modern Applied Statistical Methods, 2005, 4, 134-139Artikel i tidskrift (Refereegranskat)
  • 315.
    Almasri, Abdullah
    et al.
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för nationalekonomi och statistik.
    Shukur, Ghazi
    Clustering Using Wavelet Transformation2008Ingår i: Handbook of Research on Cluster Theory / [ed] Charlie Karlsson, Edward Elgar , 2008Kapitel i bok, del av antologi (Refereegranskat)
  • 316.
    Almered Olsson, Gunilla
    et al.
    Norges Teknisk-Naturvitenskapelige Universitet, Trondheim, Norge.
    Bladh, GabrielKarlstads universitet, Institutionen för samhällsvetenskap.Månsson, BengtKarlstads universitet, Institutionen för ingenjörsvetenskap, fysik och matematik.Nyberg, LarsKarlstads universitet, Institutionen för natur och miljö.
    Inte bara träd: hållbart mångbruk av skogslandskapet2004Samlingsverk (redaktörskap) (Refereegranskat)
    Abstract [sv]

    Skogslandskapen - hur skall vi värdera dem? Ska de betraktas som rekreationsområden och kulturlandskap eller som arena för konflikter och dragkamp om olika resurser? Är skogsregionerna närande eller tärande? Vilka viktiga samband finns mellan skandinaviska och tropiska landskap?Detta är några av de teman som behandlas i denna spänannde bok om de många dimensionerna och resurserna som ryms i skogslandskapen. Boken ger nya och stimulerande aspekter på framtidsmöjligheterna för en hållbar utveckling för boreala skogslandskap. Den tar också upp det nödvändiga mångbruket av skogens resurser liksom den förändrade synen på människans roll i skogen. Och inte minst behandlas den ekologiska paradoxen att störningar behövs för att bevara skogens ekologiska mångfald.Boken är författad av samhällsvetare, miljöteknologer och ekologer inom den tvärvetenskapliga forskargruppen MiljöFocus vid Karlstads universitet.

  • 317. Almgren, Karin
    et al.
    Leidhammar, Börje
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för juridik.
    Förenklad taxering - betänkande av skatteförenklingskommiten1985Ingår i: Skattenytt 1985, s. 408 - 418Artikel i tidskrift (Övrigt vetenskapligt)
  • 318. Almgren, Karin
    et al.
    Leidhammar, Börje
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för juridik.
    Skatteförfarandet. [D.] 11992Bok (Refereegranskat)
  • 319. Almgren, Karin
    et al.
    Leidhammar, Börje
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för juridik.
    Skatteförfarandet. D. 21996Bok (Refereegranskat)
  • 320. Almgren, Karin
    et al.
    Leidhammar, Börje
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för juridik.
    Skatteprocessen2004Bok (Refereegranskat)
  • 321. Almgren, Karin
    et al.
    Leidhammar, Börje
    Karlstads universitet, Institutionen för ekonomi.
    Walterson, Frank
    Sveriges rikes lag: 17,Skatteförfarande och skattebrott1998 (uppl. 98:1)Bok (Övrigt vetenskapligt)
  • 322. Almgren, Karin
    et al.
    Leidhammar, Börje
    Karlstads universitet, Institutionen för ekonomi.
    Walterson, Frank
    Sveriges rikes lag: Skatteförfarande och skattebrott2001 (uppl. 3 [rev.] uppl.)Bok (Övrigt vetenskapligt)
  • 323. Almgren, Karin
    et al.
    Leidhammar, Börje
    Karlstads universitet, Institutionen för ekonomi.
    Walterson, Frank
    Sveriges rikes lag: Skatteförfarande och skattebrott1999 (uppl. 1)Bok (Övrigt vetenskapligt)
  • 324. Almgren, Karin
    et al.
    Leidhammar, Börje
    Karlstads universitet, Institutionen för ekonomi.
    Walterson, Frank
    Sveriges rikes lag: Skatteförfarande och skattebrott2000 (uppl. 2 [rev.] uppl.)Bok (Övrigt vetenskapligt)
  • 325. Almgren, M
    et al.
    Alsins, J
    Mukhtar, E
    van Stam, Jan
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap. Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Materialvetenskap.
    Diffusion-Controlled Fluorescence Quenching in Micelles1989Ingår i: Reactions in Compartmentalized Liquids; Knoche W and Shomacker R (eds), Springer-Verlag, Berlin Heidelberg (1989), 61-68, 1989Kapitel i bok, del av antologi (Refereegranskat)
  • 326. Almgren, M.
    et al.
    Alsins, J.
    Mukhtar, E.
    van Stam, Jan
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap. Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Materialvetenskap.
    Fluorescence Quenching Dynamics in Rodlike Micelles1988Ingår i: J. Phys. Chem., 1988, 92, 4479-4483Artikel i tidskrift (Refereegranskat)
  • 327. Almgren, M.
    et al.
    Alsins, J.
    van Stam, Jan
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap. Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Materialvetenskap.
    Fluorescence Decay Studies of Structures and Dynamics in Ionic Micellar Solutions1988Ingår i: Ordering and Organization in Ionic Solutions, World Scientific Publishing Co Ltd, Singapore, 1988, 225-232, 1988Kapitel i bok, del av antologi (Refereegranskat)
  • 328. Almgren, M
    et al.
    Alsins, J
    van Stam, Jan
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap. Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Materialvetenskap.
    Mukhtar, E
    The micellar sphere-to-rod transition in CTAC-NaClO3. A fluorescence quenching study1988Ingår i: Progr. Colloid Polym. Sci., 1988, 76, 68-74Artikel i tidskrift (Refereegranskat)
  • 329. Almgren, M.
    et al.
    Hansson, P.
    Mukhtar, E.
    van Stam, Jan
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap. Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Materialvetenskap.
    Aggregation of Alkyltrimethylammonium Surfactants in Aqueous Poly(styrenesulfonate) Solutions1992Ingår i: Langmuir, 1992, 8, 2405-2412Artikel i tidskrift (Refereegranskat)
  • 330. Almgren, M.
    et al.
    Löfroth, J-E
    van Stam, Jan
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap. Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Materialvetenskap.
    Fluorescence Decay Kinetics in Monodisperse Confinements with Exchange of Probes and Quenchers1986Ingår i: J. Phys. Chem., 1986, 90, 4431-4437Artikel i tidskrift (Refereegranskat)
  • 331. Almgren, M.
    et al.
    van Stam, Jan
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap. Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Materialvetenskap.
    Lindblad, C.
    Li, P.
    Stilbs, P.
    Bahadur, P.
    Aggregation of Poly(ethyelene oxide)-Poly(propylene oxide)-Poly(ethylene oxide) Triblock Copolymers in the Presence of Sodium Dodecyl Sulfate in Aqueous Solution1991Ingår i: J. Phys. Chem., 1991, 95, 5677-5684Artikel i tidskrift (Refereegranskat)
  • 332. Almgren, M
    et al.
    van Stam, Jan
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemi och biomedicinsk vetenskap. Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Materialvetenskap.
    Swarup, S
    Löfroth, J-E
    Structure and Transport in the Microemulsion Phase of the System Triton X-100-Toluene-Water1986Ingår i: Langmuir, 1986, 2, 432-438Artikel i tidskrift (Refereegranskat)
  • 333. Almgren, S
    et al.
    Rantakeisu, U
    Starrin, Bengt
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för sociala studier.
    Vi måste visa att vi inte är rasister - En studie av Vålbergsskolan med utgångspunkt i Vålbergshändelserna1996Rapport (Refereegranskat)
  • 334.
    Almgren, Susanne
    Jönköping University.
    News Users’ (Dis)trust in Media Performance: Challenges to Sustainable Journalism in Times of Xenophobia2017Ingår i: What Is Sustainable Journalism?: Integrating the Environmental, Social, and Economic Challenges of Journalism / [ed] Peter Berglez, Ulrika Olausson and Mart Ots, Peter Lang Publishing Group, 2017, 1, s. 161-179Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    In this chapter, the sustainability of journalism is explored with interest in how users express trust and distrust towards professional news media. The challenges to the sustainability of journalism have social, financial and environmental tenets. The center of attention here is the social aspect of how users negotiate the end of journalism in society. Users have conflicting views on how professional news media perform, oscillating between if the responsibility of news media should be extended to coverage of conflicting issues or to enable citizens to share a common ground imprinted by solidarity. These aspects merge and manifest in news related to issues of xenophobia and solidarity. The changed financial prospects of the news industry coincide with the timing of globalization’s effects on the local scene, where people experience increasing hurdles across the world. The sustainability of journalism—considered crucial for democracy—is currently under substantial pressure. At the same time, living conditions are deteriorating around the world. People need to migrate to other societies that are becoming ever more polarized between xenophobia and solidarity. News covering this process is constructed within a professional value system that—for the sustainability of journalism—needs to be perceived as legitimate.

  • 335.
    Almgren, Susanne
    Jönköping University.
    Undoing Churnalism?: Users sharing local news on Facebook2017Ingår i: Digital Journalism, ISSN 2167-0811, E-ISSN 2167-082X, Vol. 5, nr 8, s. 1060-1079Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study investigates the types of information that users of a local news site share on Facebook. This issue relates to the idea of "churnalism", which concerns a form of weakened journalism that diminishes the ability to perform expected tasks in a democratic society. As a major social media platform, Facebook has acquired substantial influence over news dissemination, and therefore, scholarly focus needs to be directed to users as news disseminators. The manners by which users share news on Facebook indicate whether churnalism is promoted or abated through users’ interaction with online news. In this study, a quantitative content analysis illustrates how 348 news articles published on a local news site were shared 7266 times. The results show that concerns related to churnalism should be directed primarily to the fact that the news outlet only rarely provides users with opportunities to interact with serious or hard news, while lightweight news is frequently offered. Despite this, users abate churnalism in the sense that the news they prefer to share is news from in-house sources rather than from external sources. The news extensively shared covers changes in the vicinity, and health care, and has emerged from local and regional events.

  • 336.
    Almgren, Susanne
    et al.
    Jönköping University.
    Olsson, Tobias
    Lund University, Sweden.
    Commenting, sharing and tweeting news: Measuring online news participation2016Ingår i: Nordicom Review, ISSN 1403-1108, E-ISSN 2001-5119, Vol. 37, nr 2, s. 67-81Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Social plugins for sharing news through Facebook and Twitter have become increasingly salient features on news sites. Together with the user comment feature, social plugins are the most common way for users to contribute. The wide use of multiple features has opened new areas to comprehensively study users’ participatory practices. However, how do these opportunities to participate vary between the participatory spaces that news sites affiliated with local, national broadsheet and tabloid news constitute? How are these opportunities appropriated by users in terms of participatory practices such as commenting and sharing news through Facebook and Twitter? In addition, what differences are there between news sites in these respects? To answer these questions, a quantitative content analysis has been conducted on 3,444 articles from nine Swedish online newspapers. Local newspapers are more likely to allow users to comment on articles than are national newspapers. Tweeting news is appropriated only on news sites affiliated with evening tabloids and national morning newspapers. Sharing news through Facebook is 20 times more common than tweeting news or commenting. The majority of news items do not attract any user interaction.

  • 337.
    Almgren, Susanne
    et al.
    Jönköping University, Sweden.
    Olsson, Tobias
    Lund University, Sweden.
    Deltagande användare - i princip och praktik2016Ingår i: Människorna, medierna & marknaden: Medieutredningens forskningsantologi om en demokrati i förändring, Wolters Kluwer, 2016, s. 377-401Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 338.
    Almgren, Susanne
    et al.
    Jönköping University, Sweden.
    Olsson, Tobias
    Lund University, Sweden.
    ‘Let’s Get Them Involved’ . . . to Some Extent: Analyzing Online News Participation2015Ingår i: Social Media + Society, ISSN 2056-3051, E-ISSN 2056-3051, Vol. 1, nr 2, s. 1-11Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The development of social media applications, such as blogs, Facebook, and Twitter, has offered new participatory opportunities for everyday media users. This article contributes to research by looking into one specific aspect of the increasingly more participatory media ecology—the news comment feature. Drawing on a quantitative content analysis of 1,100 news pieces, as well as spaces for user comments, the article reveals both how this emerging public space is shaped by the media company and, later, appropriated by their participating users. Our analysis reveals, for instance, that the online newspaper prefers to allow users to comment on lightweight news such as sports and entertainment. The users, however, prefer to post comments on news covering changes in proximity space, politics, and health care, while also clearly ignoring the most available news pieces (sport and entertainment). In the concluding section, the discrepancy in preferences is discussed.

  • 339.
    Almlöf Ambjörnsson, Heléne
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörs- och kemivetenskaper.
    Mercerization and Enzymatic Pretreatment of Cellulose in Dissolving Pulps2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    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.

  • 340.
    Almlöf Ambjörnsson, Heléne
    et al.
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Germgård, Ulf
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Enzyme treatment of dissolving pulps as a way to improve the following dissolution of the fibres2012Konferensbidrag (Övrigt vetenskapligt)
  • 341.
    Almlöf Ambjörnsson, Heléne
    et al.
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Germgård, Ulf
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Extended Mercerization Prior to Carboxymethyl Cellulose Preparation2011Konferensbidrag (Övrig (populärvetenskap, debatt, mm))
  • 342.
    Almlöf Ambjörnsson, Heléne
    et al.
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Germgård, Ulf
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Jardeby, Kristina
    Borregaard Chemcell, Sarpsborg, Norge.
    Kreutz, Björn
    Borregaard Chemcell, Sarpsborg, Norge.
    The influence of mercerization on the degree of substitution in carboxymethyl cellulose2009Konferensbidrag (Övrig (populärvetenskap, debatt, mm))
  • 343.
    Almlöf Ambjörnsson, Heléne
    et al.
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Schenzel, Karla
    Marthin-Luther University Halle-Wittenberg.
    Germgård, Ulf
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Characterization of CMC by NIR FT Raman spectroscopy2012Konferensbidrag (Övrig (populärvetenskap, debatt, mm))
  • 344.
    Almlöf Ambjörnsson, Heléne
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörs- och kemivetenskaper.
    Östberg, Linda
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörs- och kemivetenskaper.
    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
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörs- och kemivetenskaper.
    Enzyme pretreatment of dissolving pulp as a way to improve the following dissolution in NaOH/ZnO2014Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 68, nr 4, s. 385-391Artikel i tidskrift (Refereegranskat)
  • 345.
    Almlöf, Heléne
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Extended Mercerization Prior to Carboxymethyl Cellulose Preparation2010Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Carboxymethyl cellulose (CMC) is produced commercially in a two-stage process consisting of a mercerization stage, where the pulp is treated with alkali in a water alcohol solution, followed by an etherification stage in which monochloroacetic acid is added to the pulp slurry. In this thesis an extended mercerization stage of a spruce ether pulp was investigated where the parameters studied were the ratio of cellulose I and II, concentration of alkali, temperature and retention time. The influence of the mercerization stage conditions on the etherification stage, were evaluated as the degree of substitution (DS) of the resulting CMC and the filterability of CMC dissolved in water at a concentration of 1%. The DS results suggested that the NaOH concentration in the mercerization stage was the most important of the parameters studied. When the NaOH concentration in the mercerization step was low (9%), a high cellulose II content in the pulp used was found to have no negative impact on the DS of the resulting CMC compared with pulps with only cellulose I. However, when the NaOH concentration was high (27.5%), pulps with high content of cellulose II showed a lower reactivity than those with only cellulose I with respect to the DS of the CMC obtained after a given charge of NaMCA.

    The results obtained from the filtration ability study of CMC water solutions suggested that both the amount of cellulose II in the original pulp and the temperature had a negative influence on the filtration ability whereas the NaOH concentration in the mercerization stage had a positive influence. The filtration ability was assumed to be influenced highly by the presence of poorly reacted cellulose segments. A retention time between 1-48 h in the mercerization stage had no effect on either the DS or the filtration ability of the CMC.

    Using NIR FT Raman spectroscopy molecular structures of CMC and its gel fraction were analyzed with respect to the conditions used in the extended mercerization stage. Here it was found that the alkaline concentration had a very strong influence on the following 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 yielded. Such CMC dissolved in water caused very thick and semi solid gum-like gels, probably due to an uneven distribution of substituting groups along the cellulose backbone. FT Raman spectra of CMC mercerized with alkaline concentrations at 18.25 and 27.5% in the mercerization stage indicated, however, that all of the cellulose molecules were totally transferred to CMC of high DS, i.e. between 0.88 and 1.05. When dissolved in water such CMC caused gels when they were prepared from ether pulp with a high fraction of cellulose II.

  • 346.
    Almlöf, Heléne
    et al.
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Basta, Jiri
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Germgård, Ulf
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Guo, Sanchuan
    Heijnesson-Hulten, Anette
    The Effect of Stock Storage on The Quality of Bamboo Kraft Pulp2010Ingår i: O PAPEL, ISSN 0031-1057, Vol. 72, nr 6, s. 43-53Artikel i tidskrift (Refereegranskat)
  • 347.
    Almlöf, Heléne
    et al.
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Kreutz, Bjørn
    Borregaard Chemcell, Norway.
    Jardeby, Kristina
    Borregaard Chemcell, Norway.
    Germgård, Ulf
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    The influence of extended mercerization on some properties of carboxymethyl cellulose (CMC)2012Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 66, s. 21-27Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Carboxymethyl cellulose (CMC) is produced commercially in a two stage process consisting of a mercerization stage in which the pulp is treated with alkali in a water alcohol solution and a second etherification stage whereby monochloro-acetic acid is added to the pulp slurry. In this study, the influence of the conditions of an extended mercerization stage was evaluated on the etherification stage concerning the degree of substitution (DS) and the filterability of the resulting CMC. The parameters studied were: (1) the ratio of cellulose I and cellulose II in the original pulp, (2) the concentration of alkali, (3) the temperature and (4) the retention time in the mercerization stage. The DS results indicate that the NaOH concentration in the mercerization stage is the most important among the parameters studied. When the NaOH concentration in the mercerization stage was high (27.5%), cellulose II showed a lower reactivity than cellulose I with respect to the DS obtained in the resulting CMC. The results from the filtration ability of CMC water solutions are interpreted that the amount of cellulose II in the original pulp and the temperature has a negative influence, while the NaOH concentration in the mercerization stage has a positive influence on the filtration ability. Retention time between 1 h–48 h in the mercerization stage had no effect on the DS or the filtration value. The filtration ability was assumed to be highly influenced by the presence of poorly reacted cellulose segments. The CMC samples with the lowest filtration ability at a given DS can be assumed to have the highest degree of unevenly substituted segments.

  • 348.
    Almlöf, Heléne
    et al.
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Schenzel, Karla
    Department of Natural Science III, Institute of Agriculture and Nutritional Science, Martin Luther University, Germany.
    Germgård, Ulf
    Karlstads universitet, Fakulteten för teknik- och naturvetenskap, Avdelningen för kemiteknik.
    Carboxymethyl cellulose produced at different mercerization conditions and characterized by NIR FT Raman spectroscopy and chemometric methods2013Ingår i: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 8, nr 2, s. 1918-1932Artikel i tidskrift (Refereegranskat)
  • 349. Almotasem, Ahmed
    et al.
    Bergström, Jens
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Gåård, Anders
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Krakhmalev, Pavel
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Holleboom, Thijs Jan
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    A molecular dynamic study on the influence of carbide particles in ferrite on material transfer during nanoscratching of ferritic iron2016Ingår i: Proceedings of the 10th International Tool Conference: TOOL, 10th International TOOL Conference : 04th to 07th October 2016, Bratislava, Slovakia / [ed] Simancik, Frantisek, 2016Konferensbidrag (Refereegranskat)
  • 350.
    AlMotasem, Ahmed Tamer
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Bergström, Jens
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Gåård, Anders
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Krakhmalev, Pavel
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Holleboom, Thijs Jan
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för ingenjörsvetenskap och fysik (from 2013).
    Adhesion between ferrite iron-€“iron/cementite countersurfaces: A molecular dynamics study2016Ingår i: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 103, s. 113-120Artikel i tidskrift (Refereegranskat)
    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. 

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