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How Can We Study Learning with Geovisual Analytics Applied to Statistics?
Linnea Stenliden,Mikael Jern
Future Internet , 2012, DOI: 10.3390/fi4010022
Abstract: It is vital to understand what kind of processes for learning that Geovisual Analytics creates, as certain activities and conditions are produced when employing Geovisual Anlytic tools in education. To understand learning processes created by Geovisual Analytics, first requires an understanding of the interactions between the technology, the workplace where the learning takes place, and learners’ specific knowledge formation. When studying these types of interaction it demands a most critical consideration from theoretical perspectives on research design and methods. This paper first discusses common, and then a more uncommon, theoretical approach used within the fields of learning with multimedia environments and Geovisual Analytics, the socio-cultural theoretical perspective. The paper next advocates this constructivist theoretical and empirical perspective when studying learning with multiple representational Geovisual Analytic tools. To illustrate, an outline of a study made within this theoretical tradition is offered. The study is conducted in an educational setting where the Open Statistics eXplorer platform is used. Discussion of our study results shows that the socio-cultural perspective has much to offer in terms of what kind of understanding can be reached in conducting this kind of studies. Therefore, we argue that empirical research to analyze how specific communities use various Geovisual Analytics to evaluate information is best positioned in a socio-cultural theoretical perspective.
Visual Storytelling – Knowledge and Understanding in Education
Linnéa Stenliden,Mikael Jern
Journal of Systemics, Cybernetics and Informatics , 2012,
Abstract: This paper presents an ongoing research project of use and learning with geographic information visualization and Visual Storytelling (geovisual analytics) in education. The fully developed study will be applied in school settings in order to 1) customize the application for educational purpose, 2) improve the teaching in social science and 3) study teachers and students experiences and learning. - The application "Open Statistics eXplorer" will be used to improve the students knowledge and understanding of sophisticated statistical relations, - Teachers will be able to, individually and together, develop a dynamic teaching material through storytelling, through the web, - Students will be able to, with help of powerful geographical statistics, explore statistical relations on their own. A better understanding of how educators and their students can elicit deeper user understanding and participation by exploiting dynamic web-enabled statistics visualization is of importance. Results from an usability study in this project are promising. Together with the associated science of perception in learning in relation to the use of multidimensional spatio-temporal statistical data this research will contribute to the research fields of geovisual analytics as well as educational science.
Generic Substitution Effects on Firm Level Market Shares in the Finnish Beta Blocker Market 1997Q1-2007Q4  [PDF]
Mikael Linden
Modern Economy (ME) , 2013, DOI: 10.4236/me.2013.412092

The firm level market structure of the Finnish beta blocker market in the period from 1997Q1 to 2007Q4 is analyzed with data analysis and with panel data regression methods. Four different market concentration measures are used. Although drug prices have decreased in response to the competition-enhancing generic substitution system which started on the 1st of March 2003, the firms’ observed market shares in the market have not decreased uniformly in the all market dimensions. At the drug substitution group level, policy change has led to more equal group share distributions both for the nominal sales shares and quantity sales shares compared to the pre-policy period. At the whole market level, nominal firm sales shares of the largest firms have increased during the policy era but quantity sales shares have declined. The results imply that the dominant firms’ nominal sale shares are augmented with firm-specific drug price setting power. The results challenge the European Union (EU) drug policy targeted to increase competition in the drug markets.


Effect of Microstructures and Material Compositions on Blister Formation  [PDF]
Yunan Prawoto. Jern Phye Tan Tan, Choon Yong Loh
Materials Sciences and Applications (MSA) , 2010, DOI: 10.4236/msa.2010.13025
Abstract: One of the early failures of coating is blister. Here two different coatings were applied on various materials and microstructures. The formation of the blister, and its microstructural and material dependencies were evaluated. It is concluded that general organic coating forms more severe blisters than that of the metallic effect coating. General organic coating protects the samples by insulation film while metallic coating protects by acting as galvanic protection. Therefore, the failure modes are also different, namely blister and filiform corrosion. The dependencies on the microstructures and on material types also follow the insulation film concept and galvanic protection concept.
A Guide to Population Modelling for Simulation  [PDF]
Leif Gustafsson, Mikael Sternad
Open Journal of Modelling and Simulation (OJMSi) , 2016, DOI: 10.4236/ojmsi.2016.42007
Abstract: This paper outlines the fundamentals of a consistent theory of numerical modelling of a population system under study. The focus is on the systematic work to construct an executable simulation model. There are six fundamental choices of model category and model constituents to make. These choices have a profound impact on how the model is structured, what can be studied, possible introduction of bias, lucidity and comprehensibility, size, expandability, performance of the model, required information about the system studied and its range of validity. The first choice concerns a discrete versus a continuous description of the population system under study—a choice that leads to different model categories. The second choice is the model representation (based on agents, entities, compartments or situations) used to describe the properties and behaviours of the objects in the studied population. Third, incomplete information about structure, transitions, signals, initial conditions or parameter values in the system under study must be addressed by alternative structures and statistical means. Fourth, the purpose of the study must be explicitly formulated in terms of the quantities used in the model. Fifth, irrespective of the choice of representation, there are three possible types of time handling: Event Scheduling, Time Slicing or Micro Time Slicing. Sixth, start and termination criteria for the simulation must be stated. The termination can be at a fixed end time or determined by a logical condition. Population models can thereby be classified within a unified framework, and population models of one type can be translated into another type in a consistent way. Understanding the pros and cons for different choices of model category, representation, time handling etc. will help the modeller to select the most appropriate type of model for a given purpose and population system under study. By understanding the rules for consistent population modelling, an appropriate model can be created in a systematic way and a number of pitfalls can be avoided.
Validation of Three Early Ejaculation Diagnostic Tools: A Composite Measure Is Accurate and More Adequate for Diagnosis by Updated Diagnostic Criteria
Patrick Jern, Juhana Piha, Pekka Santtila
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0077676
Abstract: Purpose To validate three early ejaculation diagnostic tools, and propose a new tool for diagnosis in line with proposed changes to diagnostic criteria. Significant changes to diagnostic criteria are expected in the near future. Available screening tools do not necessarily reflect proposed changes. Materials and Methods Data from 148 diagnosed early ejaculation patients (Mage = 42.8) and 892 controls (Mage = 33.1 years) from a population-based sample were used. Participants responded to three different questionnaires (Premature Ejaculation Profile; Premature Ejaculation Diagnostic Tool; Multiple Indicators of Premature Ejaculation). Stopwatch measured ejaculation latency times were collected from a subsample of early ejaculation patients. We used two types of responses to the questionnaires depending on the treatment status of the patients 1) responses regarding the situation before starting pharmacological treatment and 2) responses regarding current situation. Logistic regressions and Receiver Operating Characteristics were used to assess ability of both the instruments and individual items to differentiate between patients and controls. Results All instruments had very good precision (Areas under the Curve ranging from .93-.98). A new five-item instrument (named CHecklist for Early Ejaculation Symptoms – CHEES) consisting of high-performance variables selected from the three instruments had validity (Nagelkerke R2 range .51-.79 for backwards/forwards logistic regression) equal to or slightly better than any individual instrument (i.e., had slightly higher validity statistics, but these differences did not achieve statistical significance). Importantly, however, this instrument was more in line with proposed changes to diagnostic criteria. Conclusions All three screening tools had good validity. A new 5-item diagnostic tool (CHEES) based on the three instruments had equal or somewhat more favorable validity statistics compared to the other three tools, but is more in line with recently proposed diagnostic criteria.
Life before Myocardial Infarction
—A Qualitative Study of Middle-Aged Women

Carina Wennerholm, Michaela Jern, Marja-Liisa Honkasalo, Tomas Faresjö
Health (Health) , 2014, DOI: 10.4236/health.2014.620316
Abstract: The health burden of myocardial infarction is rising for middle-aged women and they are underrepresented in research of cardiovascular diseases. The aim of this qualitative study was to explore how life had been for middle-aged women before they suffered a myocardial infarction (MI). Through a health care register, we identified all women (n = 46) under 65 years of age in a defined region in southeast Sweden who had suffered an MI the past 2 years and a strategic selection of n = 16 women from these was made. These selected women were interviewed and their narratives were interpreted by qualitative content analysis. The qualitative interviews generated five general themes: “Serious life events”, “Negative affectivity”, “Loneliness”, “Being a good girl” and “Lack of control”. The interviews revealed that many of these women had been exposed to extreme and repeated traumatic life events in their lives. Many had a cynical attitude towards others, felt lonely and experienced a lack of social support. Many of these women endeavored to “be a good girl”, which was a special psychosocial phenomenon found. This study uncovered that these women before they suffered an MI were affected by a variety of psychosocial factors. The study stresses the importance of psychosocial risk factors in the assessment of middle-aged women’s risk profile for MI. A general conclusion for clinical practice is that in the assessment of the individual risk for myocardial infarction for middle-aged women, potential psychosocial factors might also be considered.
Processing of Lyocell Fiber Mat: An Alternative Renewable Reinforcement in Composite Manufacturing  [PDF]
Kayode Feyisetan Adekunle, Mikael Skrifvars
Green and Sustainable Chemistry (GSC) , 2015, DOI: 10.4236/gsc.2015.52007
Abstract: The carding of the Lyocell cellulose fiber was done with a cylindrical cross lap machine supplied by Cormatex Prato, Italy. Several mats were made by carding and needle punching in order to have a compact and well entangled mat suitable for reinforcement. The speed of the cross lap machine, the frequency of needle punching, the number of times the mat goes through needle punching, the feeding rate of the carded fiber and the depth of needle penetration determined the level of entanglement of the Lyocell fiber which ultimately increased the mechanical properties of the fiber. The good mechanical properties of the carded Lyocell fiber made it a renewable and environmentally friendly alternative as reinforcement in composite manufacturing. Compared with other jute fiber reinforced composites, the mechanical properties of the resulting Lyocell composites were found to be better. Regenerated cellulose fiber (Lyocell) composites were environmentally friendly and the mechanical properties were comparable to those of natural fibers.
Eigenvalue Asymptotics of the Even-Dimensional Exterior Landau-Neumann Hamiltonian
Mikael Persson
Advances in Mathematical Physics , 2009, DOI: 10.1155/2009/873704
Abstract: We study the Schr?dinger operator with a constant magnetic field in the exterior of a compact domain in ?2??, ??≥1. The spectrum of this operator consists of clusters of eigenvalues around the Landau levels. We give asymptotic formulas for the rate of accumulation of eigenvalues in these clusters. When the compact is a Reinhardt domain we are able to show a more precise asymptotic formula. 1. Introduction The Landau Hamiltonian describes a charged particle moving in a plane, influenced by a constant magnetic field of strength ??>0 orthogonal to the plane. It is a classical result, see [1, 2], that the spectrum of the Landau Hamiltonian consists of infinitely degenerate eigenvalues ??(2??+1), ??=0,1,2,…, called Landau levels. In this paper, we will study the even-dimensional Landau Hamiltonian outside a compact obstacle, imposing magnetic Neumann conditions at the boundary. Our motivation to study this operator comes mainly from the papers [3, 4]. Spectral properties of the exterior Landau Hamiltonian in the plane are discussed in [3], under both Dirichlet and Neumann conditions at the boundary, with focus mainly on properties of the eigenfunctions. A more qualitative study of the spectrum is done in [4], where the authors fix an interval around a Landau level and describe how fast the eigenvalues in that cluster converge to that Landau level. They work in the plane and with Dirichlet boundary conditions only. The goal of this paper is to perform the same qualitative description when we impose magnetic Neumann conditions at the boundary. Moreover, we do not limit ourself to the plane but work in arbitrary even-dimensional Euclidean space. The result is that the eigenvalues do accumulate with the same rate to the Landau levels for both types of boundary conditions; see Theorem 3.2 for the details. However, the eigenvalues can only accumulate to a Landau level from below in the Neumann setting. In the Dirichlet case they accumulate only from above. It should be mentioned that we suppose that the compact set removed has no holes and that its boundary is smooth. This is far more restrictive than the conditions imposed on the compact set in [4]. Several different perturbations of the Landau Hamiltonian have been studied in the last years; see [4–11]. They all share the common idea of making a reduction to a certain Toeplitz-type operator whose spectral asymptotics are known. We also do this kind of reduction. The method we use is based on the theory for pseudodifferential operators and boundary PDE methods, which we have not seen in any of the mentioned
Further education for staff in drug abuse treatment - a realistic approach
Mikael Sandlund
Nordic Studies on Alcohol and Drugs , 2012, DOI: 10.2478/v10199-012-0018-7
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