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  • 1.
    Al-Mulla, S Y Youssif
    University of Borås, School of Engineering.
    Spin Dependent Exchange Scattering from Ferromagnetic Materials2008Conference paper (Other academic)
  • 2.
    Alrud, Bengt
    University of Borås, School of Engineering.
    Fractal spectral measures in two dimensions2011Doctoral thesis, monograph (Other academic)
  • 3. Anderson, D.
    et al.
    Andersson, F.
    Andersson, Peter
    University of Borås, School of Engineering.
    Billander, A.
    Desaix, Mats
    University of Borås, School of Engineering.
    The optimal journey from A to B2008In: American Journal of Physics, ISSN 0002-9505, E-ISSN 1943-2909, Vol. 76, no 9, p. 863-866Article in journal (Refereed)
    Abstract [en]

    How fast can you comfortably travel between two points A and B? This question is formulated as a minimization problem of a functional where the discomfort is quantified in terms of the integral of the square of the acceleration between A and B. The problem is solved in terms of the corresponding Euler-Lagrange equation and approximately using a direct variational approach based on trial functions and Ritz optimization. The main purpose of the analysis is to introduce undergraduate students to variational calculus in an interesting and pedagogical way.

  • 4. Anderson, D
    et al.
    Desaix, Mats
    University of Borås, Faculty of Textiles, Engineering and Business.
    Introduction to direct variational and moment methods and an application to the Child–Langmuir law2015In: European journal of physics, ISSN 0143-0807, E-ISSN 1361-6404, Vol. 36, no 6Article in journal (Refereed)
    Abstract [en]

    A short introduction is given of direct variational methods and its relation to Galerkin and moment methods, all flexible and powerful approaches for finding approximate solutions of difficult physical equations. A pedagogical application of moment methods is given to the physically and technically important Child–Langmuir law in electron physics. The analysis is shown to provide simple, yet accurate, approximate solutions of the two-dimensional problem (a problem which does not allow an exact analytical solution) and illustrates the usefulness and the power of moment methods.

  • 5. Anderson, D.
    et al.
    Desaix, Mats
    University of Borås, School of Engineering.
    Lisak, M.
    Rasch, J.
    Galerkin approach to approximate solutions of some nonlinear oscillator equations2010In: American Journal of Physics, ISSN 0002-9505, E-ISSN 1943-2909, Vol. 78, no 9, p. 920-924Article in journal (Refereed)
    Abstract [en]

    An analysis based on the Galerkin method is given of some nonlinear oscillator equations that have been analyzed by several other methods, including harmonic balance and direct variational methods. The present analysis is shown to provide simple yet accurate approximate solutions of these nonlinear equations and illustrates the usefulness and the power of the Galerkin method. (C) 2010 American Association of Physics Teachers.

  • 6.
    Anderson, Dan
    et al.
    Chalmers .
    Desaix, Mats
    University of Borås, Faculty of Textiles, Engineering and Business.
    Approximate solution of a Thomas-Fermi model equation for bulk self-gravitating stellar objects in two dimensions2017In: European journal of physics, ISSN 0143-0807, E-ISSN 1361-6404, Vol. 38, p. 1-8, article id 015406Article in journal (Refereed)
    Abstract [en]

    Direct variational methods are used to find simple approximate solutions of the Thomas–Fermi equations describing the properties of self-gravitating radially symmetric stellar objects both in the non-relativistic and ultra-relativistic cases. The approximate solutions are compared and shown to be in good agreement with exact and numerically obtained solutions.

  • 7. Andersson, L
    et al.
    Petersen, G
    Johnson, P
    Ståhl, Fredrik
    University of Borås, School of Health Science.
    A web tool for finding gene candidates associated with experimentally induced arthritis in rat2005In: Arthritis Research & Therapy, ISSN 1478-6354, E-ISSN 1478-6362, Vol. 7, no 3, p. R485-R492Article in journal (Refereed)
    Abstract [en]

    Rat models are frequently used for finding genes contributing to the arthritis phenotype. In most studies, however, limitations in the number of animals result in a low resolution. As a result, the linkage between the autoimmune experimental arthritis phenotype and the genomic region, that is, the quantitative trait locus, can cover several hundred genes. The purpose of this work was to facilitate the search for candidate genes in such regions by introducing a web tool called Candidate Gene Capture (CGC) that takes advantage of free text data on gene function. The CGC tool was developed by combining genomic regions in the rat, associated with the autoimmune experimental arthritis phenotype, with rat/human gene homology data, and with descriptions of phenotypic gene effects and selected keywords. Each keyword was assigned a value, which was used for ranking genes based on their description of phenotypic gene effects. The application was implemented as a web-based tool and made public at http://ratmap.org/cgc. The CGC application ranks gene candidates for 37 rat genomic regions associated with autoimmune experimental arthritis phenotypes. To evaluate the CGC tool, the gene ranking in four regions was compared with an independent manual evaluation. In these sample tests, there was a full agreement between the manual ranking and the CGC ranking for the four highest-ranked genes in each test, except for one single gene. This indicates that the CGC tool creates a ranking very similar to that made by human inspection. The exceptional gene, which was ranked as a gene candidate by the CGC tool but not in the manual evaluation, was found to be closely associated with rheumatoid arthritis in additional literature studies. Genes ranked by the CGC tools as less likely gene candidates, as well as genes ranked low, were generally rated in a similar manner to those done manually. Thus, to find genes contributing to experimentally induced arthritis, we consider the CGC application to be a helpful tool in facilitating the evaluation of large amounts of textual information.

  • 8. Aneja, Arun
    et al.
    Pal, Rudrajeet
    University of Borås, Swedish School of Textiles.
    Militky, Jiri
    Kupka, Karel
    Kremenakova, Dana
    Torstensson, Håkan
    University of Borås, Swedish School of Textiles.
    Textile Thru the Looking Glass: A Novel Perspective2013Conference paper (Other academic)
    Abstract [en]

    Today, textiles and fiber science in US, Europe and Japan from its once lofty perch in the global economy, stands in stark contrast to its preeminent position of few decades ago. Its influence on the society as a whole has eroded enormously. Many of the synthetic fiber products that once fuelled the rapid growth of the industry have become mature commodity products now characterized by low growth and lower profit margins. To add to the current dilemma, organizational ‘health’ and growth processes are constantly threatened in this era of turbulence. Thus the drive for survival and success has translated, in recent times, to quest for resiliency – to survive and thrive in turbulences. On the other hand, most managers and academicians agree that innovation ensures superior organizational performance while recent research has shown that most resilient companies can dynamically orchestrate diverse innovation strategies. Resiliency in such a context has become a prerequisite for a sustained long term business prosperity fuelled by diverse technological innovations. This has intensified the organization’s search for differentiated products and services, processes, business models, technology, strategies etc. pushing firms to gain competitive advantage and also to develop new knowledge and innovation performance to drive sustainable growth. Organizations now follow multiple innovation strategies to pragmatically devise their innovation repertoire for delivering growth, hence, success in turbulent times while emphasizing resiliency. What does the future hold and how can we reverse the trend to achieve and sustain the impressive credentials of the past? To understand the significance of what the future may hold, and to reverse the downward spiral of the industry, we must evaluate the successes and failures of the past and come to grips with rapid global changes and turbulences currently underway. The present article seeks to explore such an inexorable phenomenon of quantifying and correlating innovation and business resiliency over a time line, from the annual financial data of 35 healthy and unhealthy companies along with 5 textile companies over a span of few decades. These are then extrapolated with certain predictive capabilities to suggest future trends and strategies for the textile companies. Learning from these companies, if adopted, will yield capacity to transform the scenario. Assessments and classification of the economic health of a company is typically made based on some quantity derived from selected indices, such as Altman’s Z-score. These methods can describe an instantaneous status, or a “time snap” of an economical subject but lack information about the time-dynamics of the assessment, which is important for investors, shareholders and the management. We suggest using historical data to estimate current trends in the form of the first and second time-derivative of the appropriate quantity in the time domain. This new information is independent on the quantity itself and beside more precise description can be used as new predictor to improve effectiveness of classification of successful and unsuccessful subjects. This approach is further discussed in this paper.

  • 9.
    Atanasiu, Dragu
    University of Borås, School of Engineering.
    Spectral Measures on Compacts of Characters of a Semigroup2010Conference paper (Refereed)
  • 10.
    Atanasiu, Dragu
    University of Borås, School of Engineering.
    The Disc Algebra and a Moment Problem2007In: Function Spaces: Fifth Conference on Function Spaces, May 16-20, 2006, Southern Illinois University, Edwardsville, Illinois, American Mathematical Society , 2007, p. 53-56Chapter in book (Other academic)
  • 11.
    Atanasiu, Dragu
    et al.
    University of Borås, Faculty of Textiles, Engineering and Business.
    Bengtsson, Anders
    University of Borås, Faculty of Textiles, Engineering and Business.
    Modern differential- och integralkalkyl2015 (ed. 1)Book (Refereed)
  • 12.
    Atanasiu, Dragu
    et al.
    University of Borås, Faculty of Textiles, Engineering and Business.
    Mikusinski, Piotr
    Department of Mathematics,University of Central Florida, Orlando, FL, USA.
    An elementary operational calculus2015In: Mathematical Gazette, ISSN 0025-5572, Vol. 99, no 544Article in journal (Refereed)
  • 13.
    Atanasiu, Dragu
    et al.
    University of Borås, School of Engineering.
    Mikusinski, Piotr
    Fourier transform of Radon measures on a locally compact group2010In: Integral transforms and special functions, ISSN 1065-2469, E-ISSN 1476-8291, Vol. 21, no 11, p. 815-821Article in journal (Refereed)
    Abstract [en]

    A space of generalized functions is constructed that allows us to generalize Bochner's theorem so that all Radon measures on a locally compact group are in a one-to-one correspondence with elements of that space of generalized functions. This defines a Fourier transform for all Radon measures on a locally compact group.

  • 14.
    Atanasiu, Dragu
    et al.
    University of Borås, School of Engineering.
    Mikusinski, Piotr
    On the fourier transform, Boehmians, and distributions2007In: Colloquium Mathematicum, ISSN 0010-1354, E-ISSN 1730-6302, Vol. 108, no 2, p. 263-276Article in journal (Refereed)
    Abstract [en]

    We introduce some spaces of generalized functions that are defined as generalized quotients and Boehmians. The spaces provide simple and natural frameworks for extensions of the Fourier transform.

  • 15.
    Atanasiu, Dragu
    et al.
    University of Borås, School of Engineering.
    Mikusinski, Piotr
    The Fourier transform of Lévy measures on a semigroup2008In: Integral transforms and special functions, ISSN 1065-2469, E-ISSN 1476-8291, Vol. 19, no 8, p. 537-543Article in journal (Refereed)
  • 16.
    Atanasiu, Dragu
    et al.
    University of Borås, School of Engineering.
    Mikusinski, Piotr
    Nemzer, Dennis
    An algebraic approach to tempered distributions2011In: Journal of Mathematical Analysis and Applications, ISSN 0022-247X, E-ISSN 1096-0813, Vol. 384, no 2, p. 307-319Article in journal (Refereed)
    Abstract [en]

    A space of pseudoquotients is introduced that is shown to be isomorphic to the space of tempered distributions on RN. The Fourier transform is defined as a map from the space of pseudoquotients to the space of tempered distributions and as a transformation on pseudoquotients.

  • 17.
    Atanasiu, Dragu
    et al.
    University of Borås, School of Engineering.
    Mikusinski, Piotr
    Siple, Angela
    Pseudoquotients on commutative Banach algebras2014In: Banach Journal of Mathematical Analysis, ISSN 1735-8787, Vol. 8, no 2, p. 60-66Article in journal (Refereed)
    Abstract [en]

    We consider pseudoquotient extensions of positive linear functionals on a commutative Banach algebra A and give conditions under which the constructed space of pseudoquotients can be identified with all Radon measures on the structure space A.

  • 18.
    Atanasiu, Dragu
    et al.
    University of Borås, School of Engineering.
    Nemzer, Dennis
    Extending the Laplace Transform2008In: Mathematics Student, ISSN 0025-5742, Vol. 77, p. 203-212Article in journal (Refereed)
  • 19.
    Beach, Dennis
    et al.
    University of Borås, School of Education and Behavioural Science.
    Player-Koro, Catarina
    University of Borås, School of Education and Behavioural Science.
    Authoritative Knowledge in Initial Teacher Education: Studying the Role of Subject Textbooks through Two Ethnographic Studies of Mathematics Teacher Education.2012In: Journal of Education for Teaching, ISSN 0260-7476, E-ISSN 1360-0540, Vol. 38, no 2, p. 115-125Article in journal (Refereed)
    Abstract [en]

    Two related ethnographic research projects on mathematics teacher education in Sweden are presented in this paper. They represent a response to recent policy developments that reaffirm the value of authoritative subject studies content as the central and most important component in the professional knowledge base of would-be teachers and concomitant increases in the amount of subject studies in teacher education. These policy changes, in Sweden at least, lack scientific research support and the article argues that these policies need to be seriously rethought, as the increased emphasis on subject content may undermine the development of key professional skills.

  • 20.
    Bengtsson, Anders
    University of Borås, School of Engineering.
    Light-front higher-helicity interactions2012In: Fortschritte der Physik. Special Issue: Proceedings of the XVIIthe European Workshop on String Theory 2011, Padua, Italy, 4-9 September 2011 (part 2), Wiley , 2012, p. 1038-1043Conference paper (Refereed)
    Abstract [en]

    The reformulation, using Fock space vertex operators, of the original light-front cubic interaction terms for higher spin gauge fields is reviewed with comments on quantum higher spin gravity. The formalism is generalized to all orders in the interaction. The ensuing recursive equations for the higher order vertices, if they can be explicitly solved, will encode all interaction data into a denumerable set of rational functions of p+, the overall transverse momentum structure being fixed already at the kinematical level. A more thorough exposition can be found in the archive.

  • 21.
    Bengtsson, Anders
    University of Borås, School of Engineering.
    Systematics of Higher-spin Light-front Interactions2012In: arXivArticle in journal (Other academic)
    Abstract [en]

    The original cubic interaction terms for higher spin gauge fields in four dimensions and their reformulation using Fock space vertex operators is reviewed. As a new result, the complete list of all cubic vertex functions in D=4 is derived. It is observed, contrary to what would have been expected, that the non-linear dynamical Poincar\'e transformations do not restrict the cubic interactions beyond what is required by kinematics. The role of the SU(1,1) algebra of tracelessness constraints is clarified. It is shown that higher spin fields couple non-minimally to gravity at the cubic level in D=4 light-front dynamics. Based on a detailed analysis of the structure of the light-front Poincar\'e algebra, the formalism is then generalized to all orders in the interaction. The interacting theory, being a deformation of the free theory, takes the form of a strongly homotopy Lie algebra. It is conjectured that the ensuing recursive equations, if they can be explicitly solved, will encode all interaction data into a denumerable set of functions of p+, the overall transverse momentum structure being fixed already at the kinematical level.

  • 22.
    Bengtsson, Anders
    et al.
    University of Borås, School of Engineering.
    Brink, Lars
    Kim, Sung-Soo
    Counterterms in Gravity in the Light-Front Formulation and a D=2 Conformal-like Summetry in Gravity2013In: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, Vol. 2013, no 3Article in journal (Other academic)
    Abstract [en]

    In this paper we discuss gravity in the light-front formulation (light-cone gauge) and show how possible counterterms arise. We find that Poincare invariance is not enough to find the three-point counterterms uniquely. Higher-spin fields can intrude and mimic three-point higher derivative gravity terms. To select the correct term we have to use the remaining reparametrization invariance that exists after the gauge choice. We finally sketch how the corresponding programme for N=8 Supergravity should work.

  • 23. Björklund, Camilla
    et al.
    Grevholm, Barbro
    Häggström, Johan
    Kjellström, Katarina
    Löfwall, Stefan
    Norén, Eva
    Olofsson, Gunilla
    Persson, Elisabeth
    University of Borås, School of Education and Behavioural Science.
    Persson, Lars-Erik
    Persson, Per-Eskil
    Riesbeck, Eva
    Taflin, Eva
    Lära och undervisa matematik: från förskoleklass till årskurs 62012Book (Other academic)
  • 24.
    Darányi, Sándor
    University of Borås, Swedish School of Library and Information Science.
    First- and second-order change as symmetry and symmetry breaking in folklore text content evolution: From Heraclitus to Lévi-Strauss2007Conference paper (Refereed)
    Abstract [en]

    We distinguish between first- and second order change and identify the former with perpetual alternation on an existential plane, the second with moving out into existential space. The first type can be demonstrated by two antagonistic processes inherent in a Markov chain of two pairs of complementary values: the chain gradually alternates between the opposite terminal states and the pattern is symmetrical. Such an existential plane catches an essential feature of Heraclitus’ philosophy, and can be illustrated by examples from classical Greek mythology. The same material also exemplifies Lévi-Strauss’ formula of myth, symmetrical in its weak and asymmetrical in 2 its canonical form. Since the weak form equals the orbit of a Klein group, we hypothesize that the canonical form, and thereby symmetry breaking, can be generated by element exchange between two respective Klein groups. The framework for such processes is text variation in folklore, described by ethnosemiotics.

  • 25.
    Darányi, Sándor
    University of Borås, Swedish School of Library and Information Science.
    Látvány és jelentés: Budapesti épuletszobrok elemzése és fejlödéstörténeti modellezése2007Conference paper (Other academic)
  • 26.
    Darányi, Sándor
    et al.
    University of Borås, Swedish School of Library and Information Science.
    Wittek, Peter
    University of Borås, Swedish School of Library and Information Science.
    Connecting the Dots: Mass, Energy, Word Meaning, and Particle-Wave Duality2012Conference paper (Refereed)
    Abstract [en]

    With insight from linguistics that degrees of text cohesion are similar to forces in physics, and the frequent use of the energy concept in text categorization by machine learning, we consider the applicability of particle-wave duality to semantic content inherent in index terms. Wave-like interpretations go back to the regional nature of such content, utilizing functions for its representation, whereas content as a particle can be conveniently modelled by position vectors. Interestingly, wave packets behave like particles, lending credibility to the duality hypothesis. We show in a classical mechanics framework how metaphorical term mass can be computed.

  • 27.
    Darányi, Sándor
    et al.
    University of Borås, Swedish School of Library and Information Science.
    Wittek, Peter
    University of Borås, Swedish School of Library and Information Science.
    On Information, Meaning, Space and Geometry2009In: Exploration of Space, Technology and Spatiality: Interdisciplinary Perspectives / [ed] Susan Turner, E. D. P. Turner, Hersey: Idea Group , 2009Chapter in book (Other academic)
    Abstract [en]

    We offer a few general considerations, with theoretical overtones, working toward the definition and generation of a geometric language for practical purposes, prominently for information retrieval. This chapter is a non-mathematical introduction to the mathematical modelling of meaning of both words and sentences, outlining already existing components of such an endeavour, and hinting at directions of synthesis.

  • 28.
    Darányi, Sándor
    et al.
    University of Borås, Swedish School of Library and Information Science.
    Wittek, Peter
    University of Borås, Swedish School of Library and Information Science.
    Dobreva, Milena
    Position paper: Adding a 5M layer to the 5S model of digital libraries.2010Conference paper (Refereed)
    Abstract [en]

    We expect radical changes in document ( rst and foremost text) representation for digital libraries (DL) leading to new applications for documents processing.

  • 29.
    Darányi, Sándor
    et al.
    University of Borås, Swedish School of Library and Information Science.
    Wittek, Peter
    University of Borås, Swedish School of Library and Information Science.
    Kitto, Kirsty
    The Sphynx's new riddle: How to relate the canonical formula of myth to quantum interaction2013Conference paper (Refereed)
    Abstract [en]

    We introduce Claude Lévi Strauss' canonical formula (CF), an attempt to rigorously formalise the general narrative structure of myth. This formula utilises the Klein group as its basis, but a recent work draws attention to its natural quaternion form, which opens up the possibility that it may require a quantum inspired interpretation. We present the CF in a form that can be understood by a non-anthropological audience, using the formalisation of a key myth (that of Adonis) to draw attention to its mathematical structure. The future potential formalisation of mythological structure within a quantum inspired framework is proposed and discussed, with a probabilistic interpretation further generalising the formula.

  • 30.
    Desaix, Mats
    et al.
    University of Borås, School of Engineering.
    Andersson, Dan
    Lisak, Mietek
    Eigenvalues of the Zakharov-Shabat scattering problem for two separated sech-shaped pulses2008In: Physics Letters A, ISSN 0375-9601, E-ISSN 1873-2429, Vol. 372, no 14, p. 2386-2390Article in journal (Refereed)
  • 31. Gustafsson, Birgit
    et al.
    Åberg-Bengtsson, Lisbeth
    University of Borås, School of Education and Behavioural Science.
    It’s just to replace this [x] with something”: Secondary-school Students’ Grappling with Algebraic Problems2011Conference paper (Refereed)
    Abstract [en]

    The present study is one part of a larger research project dealing with the teaching and learning of mathematics in the latter part of the Swedish compulsory education and the first year of upper secondary school. The focus of the project as such is upon classroom communication with respect to teacher-student interaction on the one hand and students’ interpretation and understanding of the learning content on the other. The mathematical domain that is studied is algebra, and both mathematical concepts, which are new to the students, and concepts, which students are already familiar with, are of interest. It is frequently argued that algebra is an abstract and problematic area (e.g., Olteanu, 2007; Kieran, 1992; The Swedish National Agency for Education, 1999), which most students have not encountered in primary education in any formal sense, and which contains a body of new mathematical concepts. Thus, the teaching and learning of this particular area is an urgent domain for research on mathematics education.

  • 32.
    Hallnäs, Lars
    University of Borås, Faculty of Textiles, Engineering and Business.
    On the Proof Theoretic Foundations of Set Theory2015In: Advances in Proof-Theoretic Semantics / [ed] Thomas Piecha and Peter Schroeder-Heister, Springer Science+Business Media B.V., 2015, p. 161-171Chapter in book (Refereed)
  • 33. Johannesson, Pär
    et al.
    Speckert, Michael
    Dressler, Klaus
    de Maré, Jacques
    Lorén, Sara
    University of Borås, School of Engineering.
    Ruf, Nikolaus
    Rychlik, Igor
    Streit, Anja
    Svensson, Thomas
    Evaluation of Customer Loads2013In: Guide to Load Analysis for Durablity in Vehicle Engineering / [ed] P Johannesson, M Speckert, Wiley , 2013, p. 287-320Chapter in book (Other academic)
    Abstract [en]

    The overall goal of vehicle design is to make a robust and reliable product that meets the demands of the customers and this book treats the topic of analysing and describing customer loads with respect to durability. Guide to Load Analysis for Vehicle and Durability Engineering supplies a variety of methods for load analysis and also explains their proper use in view of the vehicle design process. In Part I, Overview, there are two chapters presenting the scope of the book as well as providing an introduction to the subject. Part II, Methods for Load Analysis, describes useful methods and indicates how and when they should be used. Part III, Load Analysis in view of the Vehicle Design Process, offers strategies for the evaluation of customer loads, in particular characterization of customer populations, which leads to the derivation of design loads, and finally to the verification of systems and components.

  • 34.
    Johansson, Petter
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    Some results on amoebas and coamoebas of affine spaces2017In: Analysis Meets Geometry: The Mikael Passare Memorial Volume / [ed] Andersson, M., Boman, J., Kiselman, C., Kurasov, P., Sigurdsson, R., Cham, Switzerland: Birkhäuser Verlag, 2017, 1, p. 261-285Chapter in book (Refereed)
    Abstract [en]

    We give some topological characteristics of the coamoeba of a generic k-dimensional affine space and two stronger versions, specific for the affine case, of a result by Nisse, Sottile and the author. We also give topological and partly algebraical characterizations of the amoeba and coamoeba in some special cases: k=n-1, k=1 and, when n is even, k=n/2, in the last case with a certain emphasis on the example n=4.

  • 35.
    Kupka, Karel
    et al.
    Trilobyte Statistical Software, Ltd..
    Pal, Rudrajeet
    University of Borås, Faculty of Textiles, Engineering and Business.
    Aneja, Arun Pal
    East Carolina State University.
    Militky, Jiri
    Technical University of Liberec.
    Characterizing Business Resilience Using SVM-Based Predictive Modeling2016In: Meeting on Statistics in Business and Industry / [ed] Universitat Politècnica de Catalunya, Department of Statistics and Operations Research, Barcelona, Spain, 2016, p. 39-40Conference paper (Other academic)
    Abstract [en]

    Business resilience has gained prominence, in academia and practice, vis-à-vis the heightened challenges recently faced by organizations, e.g. financial crisis. Developing resilience by thriving or bouncing back from crises yields sound business health in the future.However extant scholarly discussion on predictive modelling of economic resilience is rather limited, while business health studies are mainly limited to bankruptcy failure predictions. These studies mostly utilize financial snapshots (based on only few years data) to construct the predictive models hence are static in nature (Balcaen and Ooghe 2006). Several assumptions underpin these static models, e.g. considering failure as a steady process devoid of organizational history (Appiah et al. 2015, du Jardin and Séverin 2011). Even though, few recent studies (cf. du Jardin and Séverin (2011), Chen et al. (2013) etc.) have designed a “trajectory of corporate collapse” to forecast the changes in firms’ financial health, using various ‘expert systems’ like self-organizing maps (SOM) based upon unsupervised neural network approach, these studies still interpret the findings largely for predicting bankruptcy (a ‘state’) rather than drawing inference on the economic growth or recovery patterns (a ‘trajectory’) of organizations – a key to generate resilience. Neither these studies utilize longitudinal financial data (spanning over many years) to capture the dynamics of corporate history required to build resilience of organizations in reality.In this context, our paper proposes developing a predictive econometric model of business resilience by using ‘expert’ SVM method. The expanded predictor based on financial ratios highlighted by Altman (1968)’s Z-score also takes into consideration the corporate dynamics (first and second derivatives). Historical financial data is gathered from 198 firms representing 26 Dow Jones industrial sectors, and starting from 1960s.Our prediction model achieved comparatively high predictive accuracy of ---- (for a forecasting horizon of ----- years) and is comparable to similar studies. However, the main contribution of the paper is in proposing four archetypical patterns in business health trajectories, derived from the historical hind-sight, defined by tendency-dynamics combinations and is essential to characterize business resilience as follows:

    Business Health (at T = t+1) = Business Health (T = 0 to t) + Resilience function

    These four typical situations range from the most pessimistic case (tendency = Down, dynamics = Down) to the most promising (Up-Up). The four archetypes can be used to explain four resilience functions, viz. (i): up-up as sustainable resilience, (ii) up-down as short-term resilience, till t = T, (iii) down-up as resilience in near-future, at t = T, and (iv) down-down as lack of resilience.

  • 36.
    Lantz, Björn
    University of Borås, School of Engineering.
    Den statistiska undersökningen: grundläggande metodik och typiska problem2011Book (Other academic)
  • 37.
    Lantz, Björn
    University of Borås, School of Engineering.
    The impact of sample non-normality on ANOVA and alternative methods2013In: British Journal of Mathematical & Statistical Psychology, ISSN 0007-1102, E-ISSN 2044-8317, Vol. 66, no 2, p. 224-244Article in journal (Refereed)
    Abstract [en]

    In this journal, Zimmerman (2004, 2011) has discussed preliminary tests that researchers often use to choose an appropriate method for comparing locations when the assumption of normality is doubtful. The conceptual problem with this approach is that such a two-stage process makes both the power and the significance of the entire procedure uncertain, as type I and type II errors are possible at both stages. A type I error at the first stage, for example, will obviously increase the probability of a type II error at the second stage. Based on the idea of Schmider et al. (2010), which proposes that simulated sets of sample data be ranked with respect to their degree of normality, this paper investigates the relationship between population non-normality and sample non-normality with respect to the performance of the ANOVA, Brown–Forsythe test, Welch test, and Kruskal–Wallis test when used with different distributions, sample sizes, and effect sizes. The overall conclusion is that the Kruskal–Wallis test is considerably less sensitive to the degree of sample normality when populations are distinctly non-normal and should therefore be the primary tool used to compare locations when it is known that populations are not at least approximately normal.

  • 38.
    Linusson, Henrik
    et al.
    University of Borås, School of Business and IT.
    Johansson, Ulf
    University of Borås, School of Business and IT.
    Löfström, Tuve
    University of Borås, School of Business and IT.
    Signed-Error Conformal Regression2014In: Advances in Knowledge Discovery and Data Mining 18th Pacific-Asia Conference, PAKDD 2014 Tainan, Taiwan, May 13-16, 2014 Proceedings, Part I, Springer , 2014, p. 224-236Conference paper (Refereed)
    Abstract [en]

    This paper suggests a modification of the Conformal Prediction framework for regression that will strengthen the associated guarantee of validity. We motivate the need for this modification and argue that our conformal regressors are more closely tied to the actual error distribution of the underlying model, thus allowing for more natural interpretations of the prediction intervals. In the experimentation, we provide an empirical comparison of our conformal regressors to traditional conformal regressors and show that the proposed modification results in more robust two-tailed predictions, and more efficient one-tailed predictions.

  • 39.
    Lorén, Sara
    et al.
    University of Borås, School of Engineering.
    de Maré, Jacques
    Maintenance for reliability: a case study2015In: Annals of Operations Research, ISSN 0254-5330, E-ISSN 1572-9338, Vol. 224, no 1Article in journal (Refereed)
    Abstract [en]

    The optimal replacement problem for components with stochastic lives has an appealing solution based on the TTT-transform. The issue is revisited for components which are regularly inspected and where statistical uncertainties are taken into account by means of the method of predicted profile likelihood. The ideas are applied on crack growth data on a low pressure nozzle in a jet engine. It turns out that the standard method is not directly applicable and that the effect of uncertainties on the replacement times is not easy to predict.

  • 40.
    Lorén, Sara
    et al.
    University of Borås, School of Engineering.
    Svensson, Thomas
    Second Moment Reliability Evaluation vs. Monte Carlo Simulations for Weld Fatigue Strength2012In: Quality and Reliability Engineering International, ISSN 0748-8017, E-ISSN 1099-1638, Vol. 28, no 8, p. 887-896Article in journal (Refereed)
    Abstract [en]

    Monte Carlo simulations have become very popular in industrial applications as a tool to study variational influences on reliability assessments. The method is appealing because it can be done without any statistical knowledge and produces results that appear very informative. However, in most cases, the information gathered is no more than a complicated transformation of initial guesses because the statistical distributions of the dominating variational influences are unknown. The seemingly informative result may then be highly misleading, in particular, when the user lacks sufficient statistical knowledge. Instead, in cases where the input knowledge of the distributional properties is vague, it may be better to use a reliability method based on the actual knowledge, often not more than second moment characteristics. This can easily be done by using a method, based on variances, covariances, and sensitivity coefficients. Here, a specific problem of fatigue life of a welded structure is studied by (i) a Monte Carlo simulation method and (ii) a second moment method. Both methods are evaluated on a fatigue strain–life approach and use experimental data showing variation in weld geometry and material strength parameters. The two methods are compared and discussed in view of the engineering problem of reliability with respect to fatigue damage.

  • 41.
    Pal, Rudrajeet
    et al.
    University of Borås, Faculty of Textiles, Engineering and Business.
    Kupka, Karel
    TriloByte Statistical Software Ltd., Czech Republic.
    Aneja, Arun
    College of Engineering & Technology, East Carolina State University, USA.
    Statistical models for rating financial performance and health of companies2015In: / [ed] College of Textiles, North Carolina State University, 2015Conference paper (Other academic)
    Abstract [en]

    Authors analyze financial data from a set of almost 200 major US companies from both manufacturing and service. The selection of the firms considered the spectrum of sectors of Dow Jones Industrial composite including manufacturing companies in aerospace & defence, automotive, beverages, footware & apparel, health technology, oil & gas and service-oriented companies like consumer services, discount stores, telecom services, insurance. Short overview of recent development in business health modelling is given. Based on the data and known expert ratings, the recently published Stagewise regression algorithm was employed to identify the most relevant predictors out of all possible financial ratios as based on the data. Support Vector Machine was used subsequently to construct a quantitative probabilistic prediction model for business investment risk evaluation. With this approach, it is possible to build less rigid, more specific models suitable for smaller sectors an shorter periods, thus allowing investors and management to better react to dynamic changes in business environment. Quantitative prediction based on Support Vector Machine (SVM) models provides more information and better decission support than traditional binary prediction (good/bad). The paper provides directly applicable parametric decission models predicting both numerical rating and good/bad classification probability  for manufacturing and service sectors. Short-term and more specific models can be used to characterize not only the business subject themselves, but also to characterize, parametrize and compare business environments.

  • 42.
    Pal, Rudrajeet
    et al.
    University of Borås, Faculty of Textiles, Engineering and Business.
    Kupka, Karel
    Trilobyte Statistical Software Ltd., Czech Republic.
    Aneja, Arun
    College of Technology and Computer Science, East Carolina University, United States.
    Militky, Jiri
    Department of Material Engineering, University of Liberec, Czech Republic.
    From classical business failure prediction models to business financial models for resilience: using advanced statistical methodologies2015In: : ICORS, 2015, p. 39-40Conference paper (Refereed)
    Abstract [en]

    Over the last 35 years business failure prediction using various methods like univariate analysis, multi-variate analysis, credit risk models etc. has become a major research domain within corporate finance (Balcaen and Ooghe 2006). These mathematical models are increasingly accepted by financial institutions, governments and the European Union in the Basel Accords (Basel II/III). However, most classic statistical failure prediction models are developed without comprehensive understanding of the nature of company failure with often arbitrarily variables chosen in an ad-hoc manner (Beaver 1967b, Cybinski 2001). In this context, the paper uses advanced statistical methodology to propose a robust business financial modeling technique. Data on 18 key financial parameters were collected for 198 US-based public companies along with their expert credit rating for 2012-13. Firstly, a correlation study was performed between Altman scores and widely accepted expert rating based on stock exchange activities. Secondly, “stage-wise” regression was conducted to select the statistically most significant candidate ratios (from 153 to 9) (Hastie et al. 2007a). Thirdly, linear regression model was employed to model the credit rating and also to reduce the candidate variables (from 9 predictor ratios to five those were statistically significant). Fourth, the significant variables were used to construct the decision plane for the linear discriminant model using support vector machine classifier (SVM-C) estimation procedure (Scholkopf et al. 1995, Vapnik 1998). Binary response variable was obtained by dividing the ratings into two groups: high rating (or “good companies”) and low rating (or “not so good companies”) by choosing an arbitrary threshold rating value. Finally a logistic regression model helped to define the probability of having high rating (i.e. greater than 5) for a given company. Findings were manifold. The correlation between the Z-score and rating was poor (0.0223 and 0.0133 respectively for manufacturing and service companies). The linear regression models, on the other hand, showed high correlation coefficient (0.64 and 0.71 respectively) between predicted and actual expert ratings. With a few exceptions, in the heavy industry sectors, data was homogeneous (found using predicted residual method). The equation of the new discriminating hyper plane created by the SVM classification model (termed as Investor Inclination Index - I3 model) was proposed which means that expert ratings can be more significantly correlated to a set of candidate financial ratios predicting it. These are: (i) Cost of Goods Sold/Total Operating Expenses, (ii) Earnings Before Interest and Taxes/Total Liabilities, (iii) Earnings Before Interest/Total Revenue, (iv) Retained Earnings/Total Revenue, and (v) Working Capital/Research and Development Expense. The paper contributes by updating the original Altman discriminant model by using a data-driven predictor selection strategy to create a general methodology for building financial models providing economic meaningfulness to the credit rating used for assessing company’s performance and health. A wider use of validated financial models will encourage corporate businesses and even SMEs to evaluate themselves internally thus allowing them to identify possible threats and improve credit rating. Future research aims to provide explicit economic meaningfulness to the individual predictor ratios so that companies can create a strategic resource model (SRM) by interpreting the I3 model to determine how to create a decision support aid for the company’s business management. Also authors aim to extend the contribution by developing a tendency-dynamic status to the financial predictor for incorporating a time-series behavior for pattern recognition. This will provide economic meaningfulness to the financial models; predict financial risk and means to be resilient.

  • 43.
    Pejlare, Johanna
    University of Borås, School of Education and Behavioural Science.
    On axioms and images in the history of Mathematics2007Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This dissertation deals with aspects of axiomatization, intuition and visualization in the history of mathematics. Particular focus is put on the end of the 19th century, before David Hilbert's (1862–1943) work on the axiomatization of Euclidean geometry. The thesis consists of three papers. In the first paper the Swedish mathematician Torsten Brodén (1857–1931) and his work on the foundations of Euclidean geometry from 1890 and 1912, is studied. A thorough analysis of his foundational work is made as well as an investigation into his general view on science and mathematics. Furthermore, his thoughts on geometry and its nature and what consequences his view has for how he proceeds in developing the axiomatic system, is studied. In the second paper different aspects of visualizations in mathematics are investigated. In particular, it is argued that the meaning of a visualization is not revealed by the visualization and that a visualization can be problematic to a person if this person, due to a limited knowledge or limited experience, has a simplified view of what the picture represents. A historical study considers the discussion on the role of intuition in mathematics which followed in the wake of Karl Weierstrass' (1815–1897) construction of a nowhere differentiable function in 1872. In the third paper certain aspects of the thinking of the two scientists Felix Klein (1849–1925) and Heinrich Hertz (1857–1894) are studied. It is investigated how Klein and Hertz related to the idea of naïve images and visual thinking shortly before the development of modern axiomatics. Klein in several of his writings emphasized his belief that intuition plays an important part in mathematics. Hertz argued that we form images in our mind when we experience the world, but these images may contain elements that do not exist in nature.

  • 44.
    Pejlare, Johanna
    University of Borås, School of Education and Behavioural Science.
    Torsten Brodén's work on the foundations of Euclidean geometry2007In: Historia Mathematica, ISSN 0315-0860, E-ISSN 1090-249X, Vol. 34, no 4, p. 402-427Article in journal (Refereed)
    Abstract [en]

    The Swedish mathematician Torsten Broden (1857-1931) wrote two articles on the foundations of Euclidean geometry. The first was published in 1890, almost a decade before Hilbert's first attempt, and the second was published in 1912. Broden's philosophical view of the nature of geometry is discussed and his thoughts on axiomatic systems are described. His axiomatic system for Euclidean geometry from 1890 is considered in detail and compared with his later work on the foundations of geometry. The two continuity axioms given are compared to and proved to imply Hilbert's two continuity axioms of 1903.

  • 45.
    Pejlare, Johanna
    et al.
    University of Borås, School of Education and Behavioural Science.
    Bråting, Kaisa
    Visualizations in mathematics2008In: Erkenntnis, ISSN 0165-0106, E-ISSN 1572-8420, Vol. 68, no 3, p. 345-358Article in journal (Refereed)
  • 46.
    Player-Koro, Catarina
    University of Borås, School of Education and Behavioural Science.
    Hype, hope and ICT in Teacher Education. A Bernsteinian perspective.2013In: Learning, Media & Technology, ISSN 1743-9884, E-ISSN 1743-9892, Vol. 38, no 1, p. 26-40Article in journal (Refereed)
    Abstract [en]

    This article draws from ethnographic data produced inside mathematics teacher education in Sweden. It explores and makes visible the ongoing process of education during workshops in information and communication technology (ICT) laboratory contexts in which student teachers were working with spreadsheet applications on the computer. The main finding is that, contrary to the intentions to renew and revitalise education, ICT in use seemed to operate as a relay in the reproduction of traditional ways of teaching and learning. However, the investigation is not one of the failures of education to make use of ICT but one that tries to distance itself from the traditional enthusiastic rhetoric, with the ambition to contribute to a more realistic discussion. Bernstein's concept of pedagogical discourse has been used. One education setting has been studied in detail.

  • 47.
    Player-Koro, Catarina
    University of Borås, School of Education and Behavioural Science.
    Hype, Hope and Reality, the paradox of ICT in education2010Conference paper (Refereed)
    Abstract [en]

    For 30 years there has been ongoing argument that developments of information and communication technology (ICT) will inevitably change education systems and practices. This innovation of education by using ICT-tools is often described as more or less self-evident with a naïve faith in the promises of new technology to enable teachers to make improvement in the content, the methods and the organisation of teaching and learning, with far-reaching influence on students’ skills and knowledge (Westera 2005; Nivala 2009). One example is ICT literacy defined as an important component in a set of generic skills that all citizens in the neo-liberal market society must possess (Kozma and Voogt 2003; Krumsvik 2009; Robertson 2003; De Castell, Bryson, and Jenson 2002). However, educational practices seem to have failed to live up to these utopian expectations and the process of integration of ICT has often been described as slow. Reasons for this lethargy has by many researchers been identified in various aspects of educational practice ranging from technical factors such as lack of technology and software in schools and the limited personal expertise of teachers in the use of ICT, to other factors, such as for example teachers’ beliefs, and knowledge about how to integrate ICT in teaching (Robertson 2003; UNESCO Launches ICT Standards Effort 2008; De Castell, Bryson, and Jenson 2002; Goktas, Yildirim, and Yildirim 2009; Govender and Govender 2009). The aim with this paper is to discuss how ethnographic methods can be used to make visible what educational technologies might offer for teaching and learning of mathematics. The paper offers critical considerations of the official discourse (described above), stemming from economic interests, exhorting the field of education to adopt and integrate information and communication technology (ICT), in teaching and learning. It calls for an alternative, reflexive and critical approach where questions about technology uses in education are emphasised. But the question is, what educationally, does ICT really offer for education? In the present study a group of student teachers were followed during 20 weeks of a mathematics course as part of a three and a half to four yearlong education. The course was followed in its entirely but the material discussed here represents participants observation together with conversional interviews with students from lab work where student teachers work with computers . One way of understanding the attractiveness of ICT for educational policy makers, is the way new technology is formulated in official discourse, by the society and its selected agents, where digital technology in many way defines society, and the position education has as a driving force of economic competiveness (Ball 2006). The argument for ICT use in education formulated in this discourse is rooted in economistic theorizing rather than in an educational theory (De Castell, Bryson, and Jenson 2002). The present study try to redress this imbalances. It uses Basil Bernstein conceptual framework about the construction of pedagogic discourse as a grammar underlying fields of production, recontextualisation and pedagogical practice. These theoretical concepts could be used to understand the process where dominant groups in society ideologically create unrealistic expectations about the effects of ICT use on teaching and learning. It does this through its concern with the intrinsic feature of pedagogic discourse, with the distinctive form and structure of what actually goes on the process of education (Bernstein 2000).

  • 48.
    Sandman, Lars
    et al.
    University of Borås, School of Health Science.
    Munthe, Christian
    Shared Decision-Making and Patient Autonomy2009In: Theoretical Medicine and Bioethics, ISSN 1573-1200, Vol. 30, no 4, p. 289-310Article in journal (Refereed)
    Abstract [en]

    In patient-centred care, shared decision-making is advocated as the preferred form of medical decision-making. Shared decision-making is supported with reference to patient autonomy without abandoning the patient or giving up the possibility of influencing how the patient is benefited. It is, however, not transparent how shared decision-making is related to autonomy and, in effect, what support autonomy can give shared decision-making. In the article, different forms of shared decision-making are analysed in relation to five different aspects of autonomy: (1) self-realisation; (2) preference satisfaction; (3) self-direction; (4) binary autonomy of the person; (5) gradual autonomy of the person. It is argued that both individually and jointly these aspects will support the models called shared rational deliberative patient choice and joint decision as the preferred versions from an autonomy perspective. Acknowledging that both of these models may fail, the professionally driven best interest compromise model is held out as a satisfactory second-best choice.

  • 49.
    Wittek, Peter
    University of Borås, Faculty of Librarianship, Information, Education and IT.
    Ncpol2sdpa – Sparse Semidefinite Programming Relaxations for Polynomial Optimization Problems of Noncommuting Variables2015In: ACM Transactions on Mathematical Software, ISSN 0098-3500, E-ISSN 1557-7295, Vol. 41, no 3Article in journal (Refereed)
    Abstract [en]

    A hierarchy of semidefinite programming (SDP) relaxations approximates the global optimum of polynomial optimization problems of noncommuting variables. Generating the relaxation, however, is a computationally demanding task, and only problems of commuting variables have efficient generators. We develop an implementation for problems of noncommuting problems that creates the relaxation to be solved by SDPA -- a high-performance solver that runs in a distributed environment. We further exploit the inherent sparsity of optimization problems in quantum physics to reduce the complexity of the resulting relaxations. Constrained problems with a relaxation of order two may contain up to a hundred variables. The implementation is available in Python. The tool helps solve problems such as finding the ground state energy or testing quantum correlations.

  • 50.
    Wittek, Peter
    University of Borås, Swedish School of Library and Information Science.
    Two-way incremental seriation in the temporal domain with three-dimensional visualization: Making sense of evolving high-dimensional data sets2013In: Computational Statistics & Data Analysis, ISSN 0167-9473, E-ISSN 1872-7352, Vol. 66, p. 193-201Article in journal (Refereed)
    Abstract [en]

    Two-way seriation is a popular technique to analyse groups of similar instances and their features, as well as the connections between the groups themselves. The two-way seriated data may be visualized as a two-dimensional heat map or as a three-dimensional landscape where colour codes or height correspond to the values in the matrix. To achieve a meaningful visualization of high-dimensional data, a compactly supported convolution kernel is introduced, which is similar to filter kernels used in image reconstruction and geostatistics. This filter populates the high-dimensional space with values that interpolate nearby elements, and provides insight into the clustering structure. Ordinary two-way seriation is also extended to deal with updates of both the row and column spaces. Combined with the convolution kernel, a three-dimensional visualization of dynamics is demonstrated on two data sets, a news collection and a set of microarray measurements.

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