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  • 101.
    Ahmadi Lewin, Fereshteh
    University of Gävle, Department of Caring Sciences and Sociology, Ämnesavdelningen för socialt arbete.
    Investigating the Religious and Spiritually-oriented Coping Strategies in the Swedish Context: A review of literature and directions for future research2001In: Illness, Crisis & Loss, ISSN 1054-1373, Vol. 9, no 4, p. 336-356Article in journal (Refereed)
  • 102.
    Ahmadi Lewin, Fereshteh
    University of Gävle, Department of Caring Sciences and Sociology, Ämnesavdelningen för socialt arbete.
    Islam och feminism: hur västerländska idéer behandlas inom islamisk feminism i Iran2000In: Sofia, ISSN 0281-8787, no 1, p. 13-21Article in journal (Refereed)
  • 103.
    Ahmadi Lewin, Fereshteh
    University of Gävle, Department of Caring Sciences and Sociology, Ämnesavdelningen för socialt arbete.
    The Late Modern Age and Adoption to Social and Value Changes in Later life2002In: Reflections on Diversity and Change in Modern Society: a Festschrift for Annick Sjögren / [ed] Nadia Banno Gomes, Botkyrka: Multicultural Centre , 2002Chapter in book (Other (popular science, discussion, etc.))
  • 104.
    Ahmadi Lewin, Fereshteh
    University of Gävle, Department of Caring Sciences and Sociology, Ämnesavdelningen för socialt arbete.
    The Meaning of Home among Elderly Immigrants: Directions for Future Research and Theoretical Development2000In: Housing Studies, ISSN 0267-3037, E-ISSN 1466-1810, Vol. 16, no 3, p. 353-370Article in journal (Refereed)
    Abstract [en]

    The paper discusses the notion that, in research on elderly immigrant housing, it is not enough to delineate the residential geography of different elderly immigrant groups or to study the economic and social reasons for their segregated habitations and exclusiveness. It is also necessary to understand, in the spatial context, the degree of integration and the differences between groups. In explaining these differences, consideration should be given to each elderly immigrant group's own value system, norms and preferences. It is argued that one necessary task in this endeavour is to gain knowledge about different elderly immigrant groups' understandings of what a home symbolises - what home means to them in the context of their particular ways of thinking and culture. From this point of view, the paper concludes that, when investigating the meaning of 'home' among elderly immigrants, an integrative theoretical approach based on an experiential perspective and a phenomenological and developmental perspective are deemed appropriate to be adopted.

  • 105.
    Ahmadi Lewin, Fereshteh
    et al.
    University of Gävle, Department of Caring Sciences and Sociology, Ämnesavdelningen för socialt arbete.
    Lewin, Bo
    Uppsala universitet.
    Sexualitet och heder: identitet i kris hos unga människor med utländsk bakgrund2003In: Ungdom, kulturmöten, identitet / [ed] Nader Ahmadi, Stockholm: Liber , 2003, 2, p. 139-158Chapter in book (Other (popular science, discussion, etc.))
  • 106.
    Ahmadi Lewin, Fereshteh
    et al.
    University of Gävle, Department of Caring Sciences and Sociology, Ämnesavdelningen för socialt arbete.
    Tornstam, Lars
    Elderly Iranian Immigrants in Sweden2000In: Proceedings Vol II: Social and Environmental Issues of Aging, Tehran: Goroh Bonoval Nikokar Publishing , 2000Chapter in book (Other (popular science, discussion, etc.))
  • 107.
    Ahmadi, Nader
    University of Gävle, Department of Caring Sciences and Sociology, Ämnesavdelningen för socialt arbete.
    Asylsökande barn med uppgivenhetssymtom: kunskapsöversikt och kartläggning2005Report (Other academic)
    Abstract [sv]

    En studie om situationen för sylsökande barn med uppgivenhetssymtom genomförd i två delar: en kunskapsöversikt och en kartläggning.

    Syftet har varit att ge en bild av såväl den internationella och nationella kunskapsnivån som problematikens omfattning och de drabbde barnens psykosociala tillstånd.

  • 108.
    Ahmadi, Nader
    University of Gävle, Department of Caring Sciences and Sociology, Ämnesavdelningen för socialt arbete.
    Asylsökande barn med uppgivenhetssymtom: trauma, kultur, asylprocess2006Report (Other academic)
  • 109.
    Ahmadi, Nader
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Social work.
    Foreword2013In: Substance Use & Misuse, ISSN 1082-6084, E-ISSN 1532-2491, Vol. 48, no 13, p. 1283-1284Article in journal (Other academic)
  • 110.
    Ahmadi, Nader
    et al.
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Social work.
    Ahmadi, Fereshteh
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Social work.
    The Use of Religious Coping Methods in a Secular Society: A Survey Study Among Cancer Patients in Sweden2017In: Illness, crisis and loss, ISSN 1054-1373, E-ISSN 1552-6968, Vol. 5, no 3, p. 171-199Article in journal (Refereed)
    Abstract [en]

    In the present article, based on results from a survey study in Sweden among 2,355 cancer patients, the role of religion in coping is discussed. The survey study, in turn, was based on earlier findings from a qualitative study of cancer patients in Sweden. The purpose of the present survey study was to determine to what extent results obtained in the qualitative study can be applied to a wider population of cancer patients in Sweden. The present study shows that use of religious coping methods is infrequent among cancer patients in Sweden. Besides the two methods that are ranked in 12th and 13th place, that is, in the middle (Listening to religious music and Praying to God to make things better), the other religious coping methods receive the lowest rankings, showing how nonsignificant such methods are in coping with cancer in Sweden. However, the question of who turns to God and who is self-reliant in a critical situation is too complicated to be resolved solely in terms of the strength of individuals’ religious commitments. In addition to background and situational factors, the culture in which the individual was socialized is an important factor. Regarding the influence of background variables, the present results show that gender, age, and area of upbringing played an important role in almost all of the religious coping methods our respondents used. In general, people in the oldest age-group, women, and people raised in places with 20,000 or fewer residents had a higher average use of religious coping methods than did younger people, men, and those raised in larger towns.

  • 111.
    Ahmadi, Nader
    et al.
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Criminology, Social Work.
    Ahmadi, Fereshteh
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Criminology, Social Work.
    Erbil, Pelin
    Oncology Clinique, Humanite Psychiatry, Istanbul, Turkey.
    Cetrez, Önver A.
    Department of Theology, Uppsala University, Stockholm, Sweden.
    Religious meaning-making coping in Turkey: a study among cancer patients2019In: Illness, crisis and loss, ISSN 1054-1373, E-ISSN 1552-6968, Vol. 27, no 3, p. 190-208Article, review/survey (Refereed)
    Abstract [en]

    The purpose of the present project has been to carry out international studies on meaning-making coping among people who have been affected by cancer in a number of societies and, thereby, to try to understand the influence of culture on use of these coping methods. Five countries—Sweden, South Korea, China, Japan, and Turkey—are included in the project. Qualitative semistructured interviews have been conducted with persons with a cancer diagnosis. The research group in each country has used, as a foundation, the interview questions developed for the Swedish study. These questions were, however, modified to better suite the sociocultural context of each participating country. The results presented here concern only Turkey and are restricted to religious coping methods. The study consists of 25 cancer patients (18 females and 7 males) between 20 and 71 years of age. The results of the study in Turkey indicated that the RCOPE (Religious Coping) methods are highly relevant for the interviewees. A sociological analysis of the study made from a cultural perspective showed clearly the importance of the idea of being tolerant (Sabr) for patients when coping with the psychological problems brought about by cancer. The study made it clear that culture plays an essential role in the choice of coping methods.

  • 112.
    Ahmadi, Nader
    et al.
    University of Gävle, Department of Caring Sciences and Sociology, Ämnesavdelningen för socialt arbete.
    Hessle, Marie
    Mannikoff, Anna
    Asylsökande barn med uppgivenhetssymtom: ett svenskt fenomen åren 2001-20062006Report (Other academic)
  • 113.
    Ahmadi, Nader
    et al.
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Social work.
    Ljungqvist, ArneSvedsäter, GöranUniversity of Gävle, Faculty of Health and Occupational Studies, Department of Health and Caring Sciences, Sports science.
    Doping and public health2016Collection (editor) (Other academic)
    Abstract [en]

    Doping – the use of performance-enhancing substances and methods – has long been a high-profile issue in sport but in recent years it has also become an issue in wider society. This important new book examines doping as a public health issue, drawing on a multi-disciplinary set of perspectives to explore the prevalence, significance and consequences of doping in wider society. It introduces the epidemiology of doping, examines the historical context, and explores the social, behavioural, legal, ethical and political aspects of doping. The book also discusses possible interventions for addressing the problem on organisational and societal levels.

  • 114.
    Ahmadi, Nader
    et al.
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Social work.
    Ljungqvist, Arne
    Svedsäter, Göran
    University of Gävle, Faculty of Health and Occupational Studies, Department of Health and Caring Sciences, Sports science.
    Introduction: Doping and Public Health2016In: Doping and Public Health / [ed] Nader Ahmadi, Arne Ljungqvist, Göran Svedsäter, Abingdon: Routledge, 2016, 1, , p. 151p. 1-10Chapter in book (Refereed)
    Abstract [en]

    The concept of “doping” is usually associated with sport, particularly elite sport. In fact, doping means the use of substances or methods that are banned in sport by the World Anti-Doping Agency (WADA) because of their potentially performance-enhancing effects. Their use is, therefore, considered to be against the fair play spirit of sport and can also include significant health risks for the user. However, the use of many doping substances is no longer limited to the world of sport. Doping substances such as anabolic androgenic steroids (AAS) are nowadays used also by people who are not competitive athletes but who want to make use of the effects of AAS in making their bodies more muscular, stronger and impressive in conformity with the current masculine body ideal. The use of AAS and similar substances appears to be growing and has been found in a range of countries previously not researched. At least, recent data obtained from customs seizures, court cases and some surveys suggest that the extent of AAS use outside sport has been underestimated, some reasons probably being an underground circulation of such drugs in the gym and fitness culture and the easy availability of them on the internet. One particular concern is the increasing use of nutritional supplements by growing segments of society. A significant percentage of these products have been shown to contain prohibited substances such as steroids that are not listed on the label. This shows that the nutritional supplement industry needs to be more strictly regulated. Until that happens, supplements of dubious value, content and quality will continue to be easily available around the world. What, then, are the possible reasons that active and health-conscious individuals are willing to take the risk to use preparations such as AAS? A review of the research shows that the most important motive behind the use of AAS outside the elite sports environment, i.e., in a fitness context, is to improve physical appearance. Although most users are boys and young and middle-aged men, also women of various ages use doping substances. Different types of slimming pills are popular among women (including hormone preparations), but possibly even more interesting are the new female fitness and appearance ideals that are connected to muscles and strength. The body has become increasingly important for saying something about who we are. The hunt for the perfect appearance creates a situation where denial instead of acceptance of one’s own body influences the individual’s self-image.

  • 115.
    Ahmadi, Nader
    et al.
    University of Gävle, Department of Caring Sciences and Sociology, Ämnesavdelningen för socialt arbete.
    Lönnback, Eva Britt
    Tvärkulturellt socialt arbete: av socialarbetare för socialarbetare2005Collection (editor) (Other academic)
  • 116.
    Ahmadi, Nader
    et al.
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Social work.
    Svedsäter, Göran
    University of Gävle, Faculty of Health and Occupational Studies, Department of Health and Caring Sciences, Sports science.
    "The winner takes it all": Individualization and Performance-Enhancing Drugs and Methods in Sport and in Society2016In: Doping and Public Health / [ed] Nader Ahmadi, Arne Ljungqvist, Göran Svedsäter, Abingdon: Routledge, 2016, 1, , p. 151p. 38-48Chapter in book (Refereed)
    Abstract [en]

    A common misconception in today's society is that everything is (or should be) rational and goal-oriented, which we summarized earlier as pragmatic rationalism. We call this pragmatic rationalism a misconception because it misses a historical fact that individuals' actions are and have never been governed entirely by rational motives. Emotional, ethical and existential considerations influence human actions extensively. Solidarity, willingness to share and even self-sacrifice and prioritizing the good of others before one's own are values that have survived many different economic cultures. Even today's extremely individualized society with its focus on reaching success and winning at any price cannot completely suppress these values. There is an inherent contradiction between the crude egoism of modern individualism and its historical development that largely has its origin in the care of humans.

  • 117.
    Ahmadi, Zahra
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    Moderating effects on the market orientation and strategic performance relationship in public housing2019In: Baltic Journal of Management, ISSN 1746-5265, E-ISSN 1746-5273Article in journal (Refereed)
    Abstract [en]

    Purpose - The purpose of this study is to examine how external factors moderate public housing companies’ market orientation and strategic performance relationship.

    Design/methodology/approach – The quantitative method was applied to data from a survey sent to 289 public housing companies in Sweden. A hierarchical, multicollinearity diagnostics–moderated regression analysis is used to test the research hypotheses.

    Findings – The results reveal moderating factors. The companies take several initiatives to inform themselves about customers’ needs and distribute the information within the company, but economic conditions, as well as market and technological turbulence in the municipalities, moderate the relationship between market orientation and strategic performance. Economic conditions make it difficult for public housing companies to strategically act based on market needs when making decisions and planning construction strategies (strategic performance).

    Research limitations/implications – This study is limited by focusing on public housing companies, a sector that differs radically from the open market. The study highlights the effects of moderating factors that are important for companies’ strategic performance and long-term construction strategies. From this limited focus, researchers might use the results to compare both similar and different market situations.

    Practical implications – The results of the study are useful for companies facing a similar market situation of external moderating constraints. The result might be used in future research related to the area in focus.

    Originality –This research adds new knowledge to market research by including the impact of economic conditions, which provide insight into how to develop and use market knowledge in real estate and public housing markets.

  • 118.
    Ahmadi, Zahra
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration. KTH, Bygg- och fastighetsekonomi.
    The role of market orientation in public housing companies: A study of MO’s effect on construction strategies2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The development of public housing companies in Sweden is strongly influenced by legal, economic, and demographic changes. The companies long tradition of taking responsibility for customer welfare in living have recently been criticized for excessive dominance over price setting, which is claimed to give them competitive advantages in the housing market. New legislation in 2011 requires financial return on investment, implying increased competition with radical changes for the companies. Because of the law, they find themselves transitioning from the role of being responsible for living conditions in Sweden to having to work in a businesslike manner with increased competition.The purpose of this dissertation is to analyze how the public housing companies’ deal with market orientation constructs and what their impact is on construction strategy choices. Theoretically, the market orientation concept is seen as a tool for companies to create superior value for the customers and influence strategic performance, which is a relationship tested and analyzed in this dissertation.The research was conducted through data collection stages using qualitative and quantitative methods. In the first stage, a qualitative pilot study was conducted with interviews of 15 managers in 11 public housing companies in central Sweden. In the second stage, two quantitative comparative studies of public and private housing companies in declining markets in central Sweden were conducted, collecting data from 23 (22 survey respondents) public and 37 private housing companies (16 respondents). In the third and final stage, two quantitative studies were conducted, collecting data from all 289 public housing companies (165 respondents) in Sweden.Results of the five studies show, firstly, that economic condition in the municipality have a major impact on the housing companies’ construction strategies, causing them to act innovatively in order to create superior customer value. Secondly, market orientation efforts contribute to competitive advantages in growing markets, while weak economic conditions limit the companies’ construction strategy choices in declining markets. After analyzing the link between market orientation constructs and construction strategy in declining markets, results showed that the public housing companies demonstrate higher responsiveness to customer demands compared to the private sector, but these have no effects on construction strategy. Thirdly, the analysis of moderating (external) and mediating (corporate social responsibility) effects on the market orientation and construction strategy relationship confirms that economic conditions in society influence construction strategy planning and decisions. The results of the mediating effects of CSR indicate that environmental and social issues have a positive influence on the market orientation and construction strategy relationship.

  • 119.
    Ahmadi, Zahra
    et al.
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    Lind, Hans
    chool of Architecture and the Built Environment, KTH, Royal Institute of Technology, Stockholm, Sweden.
    Sustainable strategies in a declining housing market: a comparative study2018In: International Journal of Management Practice, ISSN 1477-9064, E-ISSN 1741-8143, Vol. 11, no 4, p. 400-421Article in journal (Refereed)
    Abstract [en]

    The purpose of this study is first to examine and comparesustainable strategies within public and private housing companies in decliningmarkets in central Sweden. Then, the study evaluates the impact of newlegislation that requires public housing companies to act in a ‘businesslike’way, in the same way as a long-term private company. A quantitative studywas conducted based on a survey sent to 72 housing companies. The resultsshow that public housing companies are more strategy oriented than privatehousing companies. The results can be viewed as an on-going interactionprocess, where a company’s strategies affect its profit. The study aims toincrease the understanding of activities within housing companies in adeclining market that engage the companies in sustainable strategies toimprove their market knowledge and profit.

  • 120.
    Ahmadi, Zahra
    et al.
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    Sundström, Agneta
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    The market intelligence impact on strategic performance in declining markets2017In: International Journal of Applied Business and Economic Research, ISSN 0972-7302, Vol. 15, no 15, p. 457-473Article in journal (Refereed)
    Abstract [en]

    This study examines how companies in declining markets operate in the context of market intelligence, responding to customer needs and applying them tostrategic performance. A quantitative survey was sent to 214 public housing companies. The results indicate that market intelligence creates commitment and is significant. A positive relationship was found between data gathering, dissemination, and responsiveness, which indicates that the companies comprehend market needs but companies have difficult to manage construction strategies that improve strategic performance. There was a low value of strategic performance; a link between market intelligence and the chosen strategy was not confirmed. Companies know what the market wants but base their decision on previous strategic performanceon economic conditions in the municipality instead.

  • 121.
    Ahmadi, Zahra
    et al.
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    Sundström, Agneta
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    The Role of Market Intelligence in Declining Markets: Public Housing Companies in Sweden2015In: Journal of Nonprofit & Public Sector Marketing, ISSN 1049-5142, E-ISSN 1540-6997Article in journal (Other academic)
  • 122.
    Ahne, Ingemar
    et al.
    University of Gävle, Department of Education and Psychology, Ämnesavdelningen för didaktik.
    Söderhäll, Bengt
    University of Gävle, Department of Education and Psychology, Ämnesavdelningen för didaktik.
    HiG har ännu inte nått fram2002In: Gefle Dagblad, ISSN 1103-9302, Vol. 28 oktoberArticle, book review (Other (popular science, discussion, etc.))
    Abstract [sv]

    HÖGSKOLEDEBATT

    Tisdagen den 21 oktober hade Gefle Dagblad förstasidesrubriken: "Lärarutbildningen som ett dagis" Vi tycker det är en mycket olycklig formulering. Rubriken och artikeln andas fördomar mot förskolan

  • 123.
    Ahonen-Jonnarth, Ulla
    University of Gävle, Department of Mathematics, Natural and Computer Sciences, Ämnesavdelningen för datavetenskap.
    Dynamic web interface for metabolic pathways2002In: Promote IT 2002, 2002Conference paper (Other academic)
  • 124.
    Ahonen-Jonnarth, Ulla
    et al.
    University of Gävle, Department of Mathematics, Natural and Computer Sciences, Ämnesavdelningen för datavetenskap.
    Göransson, A
    Finlay, R
    Growth and nutrient uptake of ectomycorrhizal Pinus sylvestris seedlings treated with elevated Al concentrations and decreased levels of base cations2003In: Tree Physiology, ISSN 0829-318X, E-ISSN 1758-4469, Vol. 23, no 3, p. 157-167Article in journal (Other academic)
    Abstract [en]

    Models of the effects of elevated concentrations of aluminum (Al) on growth and nutrient uptake of forest trees frequently ignore the effects of mycorrhizal fungi. In this study, we present novel data indicating that ectomycorrhizal mycelia may prevent leaching of base cations and Al. Mycorrhizal and non-mycorrhizal Pinus sylvestris L. seedlings were grown in sand obtained from the B-horizon of a local forest. In Experiment 1, non-mycorrhizal seedlings and seedlings inoculated with Hebeloma cf. longicaudum (Pers.: Fr.) Kumm. ss. Lange or Laccaria bicolor (Maire) Orton were provided with nutrient solution containing 2.5 mM Al. Aluminum did not affect growth of non-mycorrhizal seedlings or seedlings inoculated with L. bicolor. Seedlings colonized by H. cf. longicaudum had the highest biomass production of all seedlings grown without added Al, but the fungus did not tolerate Al. Shoots of seedlings colonized by L. bicolor had the lowest nitrogen (N) concentrations but the highest phosphorus (P) concentrations of all seedlings. The treatments had small but significant effects on shoot and root Al concentrations. In Experiment 2, inoculation with L. bicolor was factorially combined with the addition of a complete nutrient solution, or a solution lacking the base cations K, Ca and Mg, and solutions containing 0 or 0.74 mM Al. Seedling growth decreased in response to 0.74 mM Al, but the effect was significant only for non-mycorrhizal seedlings. Mycorrhizal seedlings generally had higher P concentrations than non-mycorrhizal seedlings. Aluminum reduced P uptake in non-mycorrhizal plants but had no effect on P uptake in mycorrhizal plants. Mycorrhizal colonization increased the pH of the soil solution by about 0.5 units and addition of Al decreased the pH by the same amount. We conclude that the presence of ectomycorrhizal mycelia decreased leaching of base cations and Al from the soil.

  • 125.
    Ahonen-Jonnarth, Ulla
    et al.
    University of Gävle, Department of Mathematics, Natural and Computer Sciences, Ämnesavdelningen för datavetenskap.
    Odelstad, Jan
    University of Gävle, Department of Mathematics, Natural and Computer Sciences, Ämnesavdelningen för datavetenskap.
    Evaluation of simulations with conflicting goals with application to cleaning of young forest stands2006In: Proceedings of ISC 2006 (Forth International Industrial Simulation Conference), 2006, p. 498-503Conference paper (Other academic)
  • 126.
    Ahonen-Jonnarth, Ulla
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Odelstad, Jan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Simulation as a tool for the evaluation of forest management treatments2010In: ESM'2010 - The 2010 European Simulation and Modelling Conference / [ed] Gerrit K. Janssens, Katrien Ramaekers and An Caris, Ghent: EUROSIS-ETI , 2010, p. 426-433Conference paper (Refereed)
    Abstract [en]

    Cleaning of young forest stands is a multicriteria problem with conflicting goals. This kind of forest management treatment is performed by human beings but it is possible that this work may be performed by artificial agents in the future. The artificial agents need detailed information about how to clean a forest stand and/or what are the goals for cleaning. One problem in development of cleaning rules for artificial cleaning agents is that explicit knowledge about good cleaning results is not detailed. In this paper we present a tool for developing and testing rules and judging evaluation functions for cleaning. We illustrate this tool by presenting examples of some ways to clean forest stands in a computer environment and we present how the cleaning results can be evaluated. In order to obtain material for experiments it is also possible to simulate forest stands using this tool.

  • 127.
    Ahonen-Jonnarth, Ulla
    et al.
    University of Gävle, Department of Mathematics, Natural and Computer Sciences, Ämnesavdelningen för datavetenskap.
    Odelstad, Jan
    University of Gävle, Department of Mathematics, Natural and Computer Sciences, Ämnesavdelningen för datavetenskap.
    Simulation of cleaning of young forest stands2005Report (Other academic)
  • 128.
    Ahonen-Jonnarth, Ulla
    et al.
    University of Gävle, Department of Mathematics, Natural and Computer Sciences, Ämnesavdelningen för datavetenskap.
    Roitto, M
    Markkola, A M
    Ranta, H
    Neuvonen, S
    Effects of Nickel and Copper on Growth and Mycorrhiza of Scots Pine Seedlings Inoculated with Gremmeniella abietina2004In: Forest Pathology, ISSN 1437-4781, E-ISSN 1439-0329, Vol. 34, no 6, p. 337-348Article in journal (Other academic)
    Abstract [en]

    Scots pine (Pinus sylvestris) seedlings were planted in soil originating from two localities with different background levels of nickel and copper. In addition, some of the seedlings were exposed to additional nickel (20.5 mg Ni/l of soil) or copper (63.5 mg Cu/l of soil), or a combination of both Ni and Cu, via soil without direct shoot exposure during their second growing period. The seedlings were either irrigated with spring water (pH 6) or got only natural rain during the whole field experiment. All seedlings were inoculated with conidia of a shoot-pathogen Gremmeniella abietina during their third growing season, and harvested the following spring. Lengths of shoots of different year-classes were used as growth estimates. In roots, the proportion of fungal (assumedly mycorrhizal) biomass was estimated by measuring ergosterol concentration. Guajacol peroxidase activity was measured. Short roots were classified into two groups according to their condition and the composition of the mycorrhizal community was expressed as a proportion of morphotypes in the roots. The seedlings exposed to additional Ni had higher shoot growth than the seedlings in the other treatments. The mean Ni concentration in the roots of seedlings exposed to additional Ni was 79 p.p.m. and in other seedlings 16 p.p.m. Additional Ni also decreased the frequency of clearly senescent short roots and the proportion of the mycorrhizal morphotype with the thinnest mantle. These results indicate that the Ni exposure levels used in this experiment had some positive effects on the seedlings. The relative fungal biomass was about 6% lower (p = 0.0981) in the fine roots of seedlings treated with additional Cu. The mean Cu concentration in the roots of seedlings exposed to additional Cu was 256 p.p.m. and in other seedlings 29 p.p.m. Peroxidase activity, which was used as a general stress indicator in this study, was not affected by any of the treatments. The shoot growth and the relative biomass of fungi in the fine roots were positively correlated in all seedlings, and this correlation was stronger in seedlings exposed to additional Ni that were not irrigated compared with seedlings not exposed to additional Ni that were irrigated. The frequency of asymptomatic infections of G. abietina was positively correlated with the proportion of senescent short roots in the irrigated seedlings but not in not-irrigated seedlings. The general condition of seedlings may be an important factor for infection by G. abietina when moisture is high enough for the fungi to infect seedlings by conidia.

  • 129.
    Ahrenby, Hanna
    University of Gävle, Faculty of Education and Business Studies, Department of Culture Studies, Religious Studies and Educational Sciences, Art education.
    Everything is possible!: - what can happen when the content in art education is equal to a visual culture that young people live in and take part of in their everyday life2014In: 34th World Congress of the International Society for Education through Art (InSEA ) :  Diversity through Art, Change, Continuity, Context: Abstracts : Pecha Kucha Presentations, 2014, p. 1-Conference paper (Other academic)
    Abstract [en]

    The aim of this paper is to discuss the content of Art in lower secondary school education. What happens when the content is equal to a visual culture that young people live in and take part of in their everyday life? To be able to make a transition from traditional art education such as learning traditional art technics, to explore and work with contemporary visual culture that concerns young people to day, it is crucial to find out what kind of visual culture is relevant to teenagers to day. When I started working at the University of Gävle in Sweden I had the opportunity to look back at my own practise as an art teacher. In a project with pupils between the ages of 13 to 16 were asked to show in photographs and clarifying text, what they thought possibleto do technically in the art class classroom. The 13-year olds took photographs of objects that represented what they saw as possible to do in that classroom. After the pupils had taken, shown and commented on their photographs a discussion with the pupils about the content, possibilities and limitations that they experienced in that art class room followed. As a second part of the project pupils aged 16 were then invited to discuss the same questions. The forms of visual culture that turned out to be the most important to both groups were digital forms of pictures, such as film, photographs made with their mobile phones, and often published on social forums such as Facebook or Instagram, as well as computer games with there visually designed settings. In conclusion the photographs and the discussions following showed that when the pupils could work with a visual media that they meet in their everyday life it gave meaning to the art subject. Some even expressed that in the art class room “everything was possible”.

  • 130.
    Ahrenby, Hanna
    University of Gävle, Faculty of Education and Business Studies, Department of Culture Studies, Religious Studies and Educational Sciences, Art education.
    Får ungas visuella kultur plats i skolans bildsal?2014In: Visuella arenor och motsägelsefulla platser: Tio texter om transformativt lärande, identitet och kulturell förändring / [ed] Karlsson, Sten O, Göteborg: Daidalos, 2014, 1, p. 193-218Chapter in book (Other academic)
  • 131.
    Ahrenby, Hanna
    et al.
    University of Gävle, Faculty of Education and Business Studies, Department of Educational sciences, Art education and Educational drama.
    Silfver, Birgitta
    University of Gävle, Faculty of Education and Business Studies, Department of Educational sciences, Art education and Educational drama.
    Aesthetic learning processes2015In: 25th EECERA Annual conference 'Innovation, experimentation and adventure in early childhood': Abstract Book, 2015, p. 271-271Conference paper (Other academic)
    Abstract [en]

    The aim with our ongoing research is to find out what primary school teacher students (working with 6-8 year old pupils) thought of the meaning of aesthetics in teaching. What are the benefits of an aesthetic learning process? Previous research that we refer to is the dissertation of Tarja Häikö (2007). She investigates how aestethic learning processes are used in school and preschools. Boberg & Högberg (2015) have investigated how aestethic learning processes are used in schools and teacher education. Chemi (2012) has investigated the relationship between art, emotions and learning. Our framework is socio-cultural theory in accordance with Vygotsky (1995). The work of Gardner (2009), Hethland (2013) and Lindström (2010 & 2012) provides us with tools for analysis. The work has an hermeneutic phenomenologic research approach, using narratives (poetry as method). The participants were informed of the study and its aims. The confidentiality of the informants was secured. Consequences for informants were considered. A story can be a powerful way of reporting the results in research. How about using an even more condensed form, like a poem? We assume that the poetic language communicates with the reader in a more sensitive way than other research languages. Can the creation of the haiku in itself be a tool for discovery? We hope that the students will became aware of the usefulness and meaning of aesthetic learning. We also hope for increased use of aesthetic learning processes in schools. 

  • 132.
    Ahrenby, Hanna
    et al.
    University of Gävle, Faculty of Education and Business Studies, Department of Educational sciences, Art education and Educational drama.
    Silfver, Birgitta
    University of Gävle, Faculty of Education and Business Studies, Department of Educational sciences, Art education and Educational drama.
    Estetiska lärprocesser: vad ger det studenterna?2015Conference paper (Other academic)
  • 133.
    Ahrné, Karin
    et al.
    SLU.
    Bengtsson, Bengt Åke
    Björklund, Jan-Olof
    Cederberg, Björn
    Eliasson, Claes
    Hydén, Nils
    Jonasson, Jan
    Lindeborg, Mats
    Lst Kalmar Län.
    Ohlsson, Anders
    Palmqvist, Göran
    Ryrholm, Nils
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Biology.
    Rödlista över fjärilar Lepidoptera2015In: Rödlistade arter i Sverige 2015 / [ed] Westling, Anna, Uppsala: ArtDatabanken SLU , 2015, p. 98-112Chapter in book (Other academic)
  • 134.
    Airey, John
    et al.
    Uppsala universitet, Fysikundervisningens didaktik.
    Eriksson, Urban
    Uppsala universitet, Fysikundervisningens didaktik.
    Fredlund, Tobias
    Uppsala universitet, Fysikundervisningens didaktik.
    Linder, Cedric
    Uppsala universitet, Fysikundervisningens didaktik.
    On the Disciplinary Affordances of Semiotic Resources2014In: IACS-2014 Book of abstracts, 2014, p. 54-55Conference paper (Refereed)
    Abstract [en]

    In the late 70’s Gibson (1979) introduced the concept of affordance. Initially framed around the needs of an organism in its environment, over the years the term has been appropriated and debated at length by a number of researchers in various fields. Most famous, perhaps is the disagreement between Gibson and Norman (1988) about whether affordances are inherent properties of objects or are only present when they are perceived by an organism. More recently, affordance has been drawn on in the educational arena, particularly with respect to multimodality (see Linder (2013) for a recent example). Here, Kress et al. (2001) have claimed that different modes have different specialized affordances. Then, building on this idea, Airey and Linder (2009) suggested that there is a critical constellation of modes that students need to achieve fluency in before they can experience a concept in an appropriate disciplinary manner. Later, Airey (2009) nuanced this claim, shifting the focus from the modes themselves to a critical constellation of semiotic resources, thus acknowledging that different semiotic resources within a mode often have different affordances (e.g. two or more diagrams may form the critical constellation).

    In this theoretical paper the concept of disciplinary affordance (Fredlund et al., 2012) is suggested as a useful analytical tool for use in education. The concept makes a radical break with the views of both Gibson and Norman in that rather than focusing on the discernment of one individual, it refers to the disciplinary community as a whole. Put simply, the disciplinary affordances of a given semiotic resource are determined by those functions that the resource is expected to fulfil by the disciplinary community. Disciplinary affordances have thus been negotiated and developed within the discipline over time. As such, the question of whether these affordances are inherent or discerned becomes moot. Rather, from an educational perspective the issue is whether the meaning that a semiotic resource affords to an individual matches the disciplinary affordance assigned by the community. The power of the term for educational work is that learning can now be framed as coming to discern the disciplinary affordances of semiotic resources.

    In this paper we will briefly discuss the history of the term affordance, define the term disciplinary affordance and illustrate its usefulness in a number of educational settings.

  • 135.
    Airey, John
    et al.
    Uppsala universitet, Fysikundervisningens didaktik.
    Eriksson, Urban
    Uppsala universitet, Fysikundervisningens didaktik.
    Fredlund, Tobias
    Uppsala universitet, Fysikundervisningens didaktik.
    Linder, Cedric
    Uppsala universitet, Fysikundervisningens didaktik.
    The Concept of Disciplinary Affordance2014Conference paper (Refereed)
    Abstract [en]

    Since its introduction by Gibson (1979) the concept of affordance has been discussed at length by a number of researchers. Most famous, perhaps is the disagreement between Gibson and Norman (1988) about whether affordances are inherent properties of objects or are only present when perceived by an organism. More recently, affordance has been drawn on in the educational arena, particularly with respect to multimodality (see Linder (2013) for a recent example). Here, Kress et al (2001) claim that different modes have different specialized affordances.

     

    In this theoretical paper the concept of disciplinary affordance (Fredlund et al., 2012) is suggested as a useful analytical educational tool. The concept makes a radical break with the views of both Gibson and Norman in that rather than focusing on the perception of an individual, it focuses on the disciplinary community as a whole. Put simply, the disciplinary affordances of a given semiotic resource are determined by the functions that it is expected to fulfil for the discipline. As such, the question of whether these affordances are inherent or perceived becomes moot. Rather, the issue is what a semiotic resource affords to an individual and whether this matches the disciplinary affordance. The power of the term is that learning can now be framed as coming to perceive the disciplinary affordances of semiotic resources.

     

    In this paper we will discuss the history of the term affordance, define the term disciplinary affordance and illustrate its usefulness in a number of educational settings.

     

    References

    Airey, J. (2009). Science, Language and Literacy. Case Studies of Learning in Swedish University Physics. Acta Universitatis Upsaliensis. Uppsala Dissertations from the Faculty of Science and Technology 81. Uppsala  Retrieved 2009-04-27, from http://publications.uu.se/theses/abstract.xsql?dbid=9547

    Fredlund, T., Airey, J., & Linder, C. (2012). Exploring the role of physics representations: an illustrative example from students sharing knowledge about refraction. European Journal of Physics, 33, 657-666.

    Gibson, J. J. (1979). The theory of affordances The Ecological Approach to Visual Perception (pp. 127-143). Boston: Houghton Miffin.

    Kress, G., Jewitt, C., Ogborn, J., & Tsatsarelis, C. (2001). Multimodal teaching and learning: The rhetorics of the science classroom. London: Continuum.

    Linder, C. (2013). Disciplinary discourse, representation, and appresentation in the teaching and learning of science. European Journal of Science and Mathematics Education, 1(2), 43-49.

    Norman, D. A. (1988). The psychology of everyday things. New York: Basic Books.

     

     

  • 136.
    Akander, Jan
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Moshfegh, Bahram
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system. Department of Management and Engineering, Division of Energy Systems, Linköping University.
    Assessing the Myths on Energy Efficiency When Retrofitting Multifamily Buildings in a Northern Region2017In: Sustainable High Rise Buildings in Urban Zones: Advantages, Challenges, and Global Case Studies / [ed] Ali Sayigh, Cham: Springer Publishing Company, 2017, 1, p. 139-161Chapter in book (Other academic)
    Abstract [en]

    In the light of EU’s requirements to achieve a major cut in energy use by 2050, Sweden has the same target. The built environment must by 2020 reduce energy use by 20 and 50 % by 2050. The size of the future building stock will naturally increase and regardless of how energy efficient future buildings will be, the energy performance of the old stock must be improved in order to reach those goals. In major renovation projects involving multifamily buildings in large residential areas in the cities, 50 % reduction can be achieved. This is cost-effective and profitable even if the rent is increased.

    Gävleborg is a sparse region in the North, with few cities. Multifamily buildings are generally much smaller than in large cities and owners are reluctant to impose changes that increase rents due to the housing situation in the region. In consequence, the Regional Council and the University of Gävle set out to assess the potential and feasibility of reducing energy use and carbon dioxide emissions in this region’s multifamily buildings. Eleven real buildings were investigated, each having various ownership forms, different technical attributes and heating sources. Energy audits and measurements were conducted to assess the condition of each building. Performances of the buildings and proposed improvements were simulated with building energy simulation programs, whilst life cycle cost analyses were conducted to study viability. Carbon dioxide emission (CO2) reductions were estimated for each improvement.

    Based on the results, a concluding discussion is made on whether or not some myths on energy use and retrofitting are true. The following is concluded: It is possible to reach a 50 % reduction, but it is not economical with the costs involved and with today’s energy prices and moderate price increase over time.

    Retrofitting or improvements made in the building’s services systems (HVAC) are more economical than actions taken to improve performance of building by constructions. HVAC improvements give about 20 % reduction in energy use. However, mechanical ventilation systems with heat recuperation are not economical, though these may or may not substantially reduce use of thermal energy.

    Solar energy is, despite the latitude of the region, economically viable—especially PV solar energy. Photovoltaic panels (PVs) are becoming viable—the combination of PVs and district heating is beneficial since saving electricity is more important than thermal energy in district-heated areas.

  • 137.
    Akander, Jan
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Morberg, Åsa
    University of Gävle, Faculty of Education and Business Studies, Department of Educational sciences, Educational science.
    Sustainability of world heritage: who inherits the ownership of decorated farmhouses of Hälsingland?2017In: A Good Life for All: Essays on sustainability celebrating 60 years of making life better / [ed] Fagerström, Arne and Cunningham, Gary M., Mjölby: Atremi AB , 2017, 1, p. 139-161Chapter in book (Other academic)
    Abstract [en]

    This chapter discusses sustainability of Sweden’s most recent World Heritage (WH) site, the Decorated Farmhouses of Hälsingland. A general overview presents what WH is, why it is special and why it should be preserved for future generations. The views of WH farm owners on managing a WH site and how they feel about the task have been assessed. WH must be preserved for future generations and it is necessary for the farms to interact sustainably with their local communities. Most WH farms are privately owned and have been within the same family for centuries. Will this continue in the future or are there problems with succession?

  • 138.
    Akander, Jan
    et al.
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för byggnadskvalitet.
    Stojanovic, Bojan
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för byggnadskvalitet.
    Hallberg, Daniel
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för byggnadskvalitet.
    Simulated Long-term Thermal Performance of a Building That Utilizes a Heat Pump System and Borehole2008In: Durability of Building Materials & Components 11: Globality and Locality in Durability / [ed] A. Nil Türkeri, Özkan Sengül, Istanbul, Turkey: Istanbul Technical University, 2008Conference paper (Refereed)
    Abstract [en]

    Over the last decades, installation and use of heat pumps has grown rapidly in Sweden, to the extent that these mainly or partly heat roughly 25 % of the heated floor space in single-family houses. A majority are ground coupled where the heat exchanger is a borehole of 60-220 m depth. As the heat pump system operates, heat extraction will in time reduce borehole temperatures, rendering lowered efficiency of the heat pump system thus directly affecting its economical and environmental aspects. Within the building sector, durability and life performance dynamics of energy systems is often not reflected upon. System performance and efficiency is assumed to be static over time, changing only due to different operation scenarios. This paper serves to quantify the long-term thermal performance degradation of a component, in this case the borehole, and how the degradation of this component affects performance-over-time of an entire system, in this case the heating system of the building. A dynamic thermal simulation model is used to assess the long-term thermal performance of the borehole. The building, which the heat pump serves, is assumed to be a typical Swedish house with normal energy consumption. Simulation results show that the depth of the borehole is of great importance to limit over-time temperature drops. The efficiency of the heat pump system is directly dependent of temperatures in the borehole. How the overall system performance is affected by component performance degradation, is highlighted.

  • 139.
    Al Amin, A.
    et al.
    Department of EEE, Uttara University, Dhaka, Bangladesh.
    Islam, M.
    Department of EEE, Uttara University, Dhaka, Bangladesh.
    Masud, M. A.
    Department of EEE, Uttara University, Dhaka, Bangladesh.
    Khan, N. H.
    Department of EEE, Uttara University, Dhaka, Bangladesh.
    Zavala, J. W. A.
    Characterization Engineer, Radio Semiconductor Corporation, Netherlands.
    Minhaz-Ul-Islam, Mohammed
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Design and performance analysis of 3.4 ghz rectangular microstrip patch antenna for wireless communication systems2017In: International Journal on Communications Antenna and Propagation, ISSN 2039-5086, E-ISSN 2039-5094, Vol. 7, no 1, p. 80-86Article in journal (Refereed)
    Abstract [en]

    Wireless communication provides low-cost, high-speed and flexible communication in present days. Hence antenna plays a vital role in the wireless communication sector. The main concern of this paper is therefore to design a 3.4 GHz rectangular Microstrip patch antenna. Moreover, the feed probe based rectangular patch antenna will be designed. The performance of the designed rectangular patch antenna will be evaluated by analysing the major parameters of the simulation results. Hence the radiation pattern, gain, impedance matching and reflection coefficient or return loss calculation will be executed by the HFSS software to evaluate the performance of the antenna. 

  • 140.
    Alayón Glazunov, Andrés
    et al.
    Division of Electromagnetic Engineering, Royal Institute of Technology (KTH), Stockholm, Sweden.
    Prasad, Sathyaveer
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. Signal Processing Lab, KTH Royal Institute of Technology, Stockholm, Sweden.
    Händel, Peter
    ACCESS Linnaeus Centre; Signal Processing Lab, KTH Royal Institute of Technology, Stockholm, Sweden.
    Experimental Characterization of the Propagation Channel along aVery Large Virtual Array in a Reverberation Chamber2014In: Progress in Electromagnetics Research B, ISSN 1937-6472, E-ISSN 1937-6472, Vol. 59, p. 205-217Article in journal (Refereed)
    Abstract [en]

    We show that the combined use of radio frequency absorbers and directive antennas can produce significant changes of the radio propagation channel properties along the positions of a virtual array inside a reverberation chamber. A multidimensional characterization of the channel was performed at 40 antenna positions with spacing of 0:233λ at 1 GHz. The average power, the Ricean K-factor, the coherence bandwidth, the r.m.s. delay spread, the mean delay, the beamforming power angle spectrum and array antenna correlation have been studied for different arrangements in the reverberation chamber. The analysis shows that the joint average over time and frequency channel behavior is, as expected, rather homogeneous along the very large array. However, individual realizations of the channel present a pronounced selective behavior in space, time and frequency with parameters varying along the positions of the virtual array suggesting that a heterogeneous behavior of the radio channels can be emulated in reverberation chambers. An important application of the presented study comprises testing of antenna array designs and algorithms in multipath environments. Further development may lead to Over The Air testing of Multiple Input Multiple Output antenna systems of various sizes, i.e., from small to very large arrays.

  • 141.
    Albert, Frederic
    et al.
    Laboratoire de Neurobiologie Humaine, Université de Provence, Marseille, France.
    Bergenheim, Mikael
    University of Gävle, Centre for Musculoskeletal Research. Department of Surgery, Central Hospital Karlstad, Karlstad, Sweden.
    Ribot-Ciscar, Edith
    Laboratoire de Neurobiologie Humaine, Université de Provence, Marseille, France.
    Roll, Jean-Pierre
    Laboratoire de Neurobiologie Humaine, Université de Provence, Marseille, France.
    The Ia afferent feedback of a given movement evokes the illusion of the same movement when returned to the subject via muscle tendon vibration2006In: Experimental Brain Research, ISSN 0014-4819, E-ISSN 1432-1106, Vol. 172, no 2, p. 163-174Article in journal (Refereed)
    Abstract [en]

    The aim of the present study was to further investigate the contribution of primary muscle spindle feedback to proprioception and higher brain functions, such as movement trajectory recognition. For this purpose, complex illusory movements were evoked in subjects by applying patterns of muscle tendon vibration mimicking the natural Ia afferent pattern. Ia afferent messages were previously recorded using microneurographic method from the six main muscle groups acting on the ankle joint during imposed "writing like" movements. The mean Ia afferent pattern was calculated for each muscle group and used as a template to pilot each vibrator. Eleven different vibratory patterns were applied to ten volunteers. Subjects were asked both to copy the perceived illusory movements by hand on a digitizing tablet and to recognize and name the corresponding graphic symbol. The results show that the Ia afferent feedback of a given movement evokes the illusion of the same movement when it is applied to the subject via the appropriate pattern of muscle tendon vibration. The geometry and the kinematic parameters of the imposed and illusory movements are very similar and the so-called "two-thirds power law" is present in the reproduction of the vibration-induced illusory movements. Vibrations within the "natural" frequency range of Ia fibres firing (around 30 Hz) produce clear illusions of movements in all the tested subjects. In addition, increasing the mean frequency of the vibration patterns resulted in a linear increase in the size of the illusory movements. Lastly, the subjects were able to recognize and name the symbols evoked by the vibration-induced primary muscle spindle afferent patterns in 83% of the trials. These findings suggest that the "proprioceptive signature" of a given movement is associated with the corresponding "perceptual signature". The neural mechanisms possibly underlying the sensory to perceptual transformation are discussed in the general framework of "the neuronal population vector model".

  • 142. Albert, Frederic
    et al.
    Ribot-Ciscar, Edith
    Fiocchi, Michel
    Bergenheim, Mikael
    University of Gävle, Belastningsskadecentrum.
    Roll, Jean-Pierre
    Proprioceptive feedback in humans expresses motor invariants during writing.2005In: Experimental Brain Research, ISSN 0014-4819, E-ISSN 1432-1106, Vol. 164, no 2, p. 242-9Article in journal (Refereed)
    Abstract [en]

    Proprioceptive feedback from populations of muscle spindle afferents feeds the brain with information relating to the instantaneous velocity and direction of ongoing movements. In this paper, we investigate whether the invariant relationship between the velocity and curvature of a trajectory, i.e. the two-thirds power law, is reflected in this muscle spindle feedback. Sixty unitary muscle spindle afferents from six ankle muscle groups were recorded using intraneural microelectrodes during imposed "writing-like" movements. The movements had kinematic parameters obeying the two-thirds power law and were imposed so that the tip of the foot followed trajectories forming four different letters and six numbers. The responses of the muscle spindle afferent populations were analysed using the population vector model. The results demonstrate that the neuronal trajectories attained from populations of muscle spindles clearly depict the path and kinematic parameters and express the movement invariants, i.e. the trajectory segmentation into units of action and the two-thirds power law. The central vs peripheral origin of such constraints involved in the motor system is discussed.

  • 143.
    Albertzeth, Gustav
    et al.
    Department of Industrial Engineering, Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia.
    Pujawan, I. Nyoman
    Department of Industrial Engineering, Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia.
    Hilletofth, Per
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production. Department of Industrial Engineering and Management, School of Engineering, Jönköping University, Jönköping, Sweden.
    Tjahjono, Benny
    Centre for Business in Society, Coventry University, Coventry, United Kingdom.
    Mitigating transportation disruptions in a supply chain: a cost-effective strategy2019In: International Journal of Logistics, ISSN 1367-5567, E-ISSN 1469-848XArticle in journal (Refereed)
    Abstract [en]

    Transportation disruptions can be damaging to a supply chain because goods may not arrive on time and this jeopardises the service level to the customers. While supply chain disruptions have gained significant attention from scholars, little has been done to explore these disruptions in the context of transportation. The study described in this paper aims to address disruptions occurring in the transportation of goods from a plant to a distribution centre. We modelled this real case to obtain insights on the effectiveness of different strategies to mitigate transportation disruptions. We evaluated four mitigation strategies and compared the outcomes in terms of service level and total costs: (1) the risk acceptance strategy, (2) the redundant stock strategy, (3) the flexible route strategy, and (4) the redundant-flexibility strategy. The results suggest that the best strategy differs depending on the budget that managers are willing to deploy to improve the service level. The simulation experiments and the use of the Incremental Cost Effectiveness Ratio (ICER) would be instrumental in helping decision makers in selecting the best disruption mitigation strategies where the best option would likely be different under varying circumstances. 

  • 144.
    Albin, Maria
    et al.
    Institutet för miljömedicin, Karolinska institutet, Stockholm.
    Abrahamsson, Kenneth
    Institutionen för ekonomi, teknik och samhälle, Luleå tekniska universitet, Luelå.
    Lagerlöf, Elisabeth
    Info2you.
    Mathiassen, Svend Erik
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research.
    Symposium: Hållbart arbetsliv i framtidens Europa – lägesrapport och utmaningar inför nästa EU ramprogram FP92018In: FALF KONFERENS 2018 Arbetet – problem eller potential för en hållbar livsmiljö?   10-12 juni 2018 Gävle: Program och abstracts / [ed] Lindberg, Per, Gävle: Gävle University Press , 2018, p. 98-99Conference paper (Refereed)
    Abstract [sv]

    Under senaste året har det inom EU pågått ett rådslag om en europeisk pelare för sociala rättigheter som syftat till ett fungerande samspel mellan social trygghet och ekonomisk förändring. Ett toppmöte för rättvisa jobb och tillväxt ägde rum i Göteborg hösten 2017, som fokuserade på hur man kan främja inkluderande tillväxt, skapa rättvisa jobb och främja lika möjligheter för alla kvinnor och män. Vid mötet redovisades också erfaren-heter av arbetslivspolitik och praktiska insatser från olika EU länder.

    Uppmärksamhet ägnades också områden som nya arbetsformer, förutsättningar för flexibilitet och trygghet, samspelet mellan löner, arbetsförhållanden, arbetsmiljö. Vidare berördes balansen mellan social trygghet och socialt skydd å ena sidan och produktivitet, ekonomisk utveckling och tillväxt å den andra. De bestående skillnaderna mellan män och kvinnor avseende anställning, arbetsförhållanden, karriärmöjligheter, lön och pension uppmärksammades också. Effekter av att befolkningen åldras eller av automatisering och digitalisering var ett annat policyområde. Sammantaget lyfte toppmötet fram strategiska frågor för den framtida arbetslivsforskningen på europeiskt plan – i denna utmaning ligger också att öka samspelet mellan forskning i Sverige och forskning i Europa.

    Svensk arbetslivsforskning behöver synas mer i ett europeiskt sammanhang och europeisk forskning och kunskapsutveckling bör bättre tas tillvara i Sverige. Med stöd av VINNOVA startades år 2013 en påverkansplattform för att lyfta fram hållbart arbetsliv som ett centralt och övergripande område i EU:s åttonde ramprogram för forskning, Horisont 2020. Motiven därtill är uppenbara; digitalisering, globalisering och en ny demografi med ökad livslängd och migration. Vi lever också i en tid med snabbare om-ställning i arbetslivet och där de traditionella arbetsmarknadsrelationerna tenderar att luckras upp.

    Syftet med denna session är dels att rapportera vad som gjorts i det Vinnova-finansierade projektet om hållbart arbetsliv i EU som nu avslutas under 2018, dels lyfta och dryfta idéer och förslag om vilken roll hållbart arbetsliv kan spela inom FP 9 – det nästa ramprogrammet som startar 2021. När det gäller det första syftet handlar det om att utveckla kontakter med EU:s institutioner som DG research, Eurofound och EU_OSHA, liksom med de europeiska arbetsmiljöforskningsinstitutionerna via PEROSH, samt forskarnätverk och parter i Europa. En annan metod har varit att ge förslag på områden som borde lyftas fram i kommande utlysningar, vilket har skett genom workshops i Bryssel och annorstädes. Vi har också verkat för att svenska forskare i ökad utsträckning kan medverka i EU-finansierade projekt, exempelvis genom att ta initiativ till forsknings-program eller delta som partner i nätverk som koordineras av forskare på europeiskt plan. Sedan något år tillbaka har en diskussion startats om FP9 – EU:s nionde ramprogram för forskning. Diskussionen utgår från professor Mariana Mazzucatos rapport Mission Oriented Research & Innovations in the European Union: A problem-solving approach to fuel innovation-led growth. Vid seminariet ges också en lägesbild om vad som är på gång i detta sammanhang både via formella och informella kanaler. Sessionen bygger vidare på en workshop som projektet genomförde i Stockholm i början av november 2017 – se:

    - www.sustainablework220.se

    - https://ec.europa.eu/info/sites/info/files/mazzucato_report_2018.pdf

  • 145.
    Aleksandrov, A. A.
    et al.
    St Petersburg State University, Russia.
    Deinekina, T. S.
    St Petersburg State University, Russia.
    Mathiassen, Svend Erik
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research.
    Lyskov, Eugene B.
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research.
    ВЛИЯНИЕ НАБЛЮДЕНИЯ ЗА ДВИЖЕНИЕМ НА ВОССТАНОВЛЕНИЕ РАБОТОСПОСОБНОСТИ ПОСЛЕ ФИЗИЧЕСКОГО УТОМЛЕНИЯ [The influence of movement's observation on recuperation after physical fatigue]2014In: Zurnal vyssej nervnoj deâtel'nosti im. I.P. Pavlova, ISSN 0044-4677, Vol. 64, no 5, p. 481-487Article in journal (Refereed)
    Abstract [en]

    The study aim was to investigate effects of mental activity, accompanied by mu-rhythm depression, on recuperation after physical fatigue. In a study participants performed 11 one minute bouts of static hand grip intermitted by 2 minutes rest pauses. During pauses participants watched video with either dynamic hand grips (biological movements) or deformation of geometric figure (control). Obtained data showed there was a significant depression of mu-rhythm during biological movement's observation. There was significant fatigue of subjects in an exercise with physical activity, but there was no reliable influence of performed mental activity on recovery after fatigue.

  • 146.
    Alieva, Jamila
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    von Haartman, Robin
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Digital collaboration within the supply chain: new booster for hidden lean potential2019Conference paper (Other academic)
    Abstract [en]

    This paper explores the hidden lean potential exposed by manufacturers’ usage of enterprise resource planning (ERP) systems. The potential can be classified into three types: unlocked lean potential in a connected ERP system, unlocked lean potential in an un-connected ERP system, and the lean potential for further unlocking in companies that do not use ERP systems when collaborating with suppliers/customers. Empirical data is obtained from two cases of manufacturing companies in Sweden and one ERP system company. The findings indicate that hidden lean potential can be unlocked through digital collaboration within the supply chain.

  • 147.
    Alizadeh, Mahmoud
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. KTH, Teknisk informationsvetenskap.
    Characterisation, Modelling and Digital Pre-Distortion Techniques for RF Transmitters in Wireless Systems2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Wireless systems have become an inevitable part of modern technologies serving humankind. The rapid growth towards large dimensional systems, e.g. 5th generation (5G) technologies, incurs needs for improving the performance of the systems and considering aspects to make them as far as possible environmentally friendly in terms of power efficiency, cost, and so on. One of the key parts of every wireless communication system is the radio frequency (RF) power amplifier (PA), which consumes the largest percentage of the total energy. Hence, accurate models of RF PAs can be used to optimize their design and to compensate for signal distortions. This thesis starts with two methods for frequency-domain characterisation to analyse the dynamic behaviour of PAs in 3rd-order non-linear systems. Firstly, two-tone signals superimposed on large-signals are used to analyse the frequency-domain symmetry properties of inter-modulation (IM) distortions and Volterra kernels in different dynamic regions of RF PAs in a single-input single-output (SISO) system. Secondly, three-tone signals are used to characterise the 3rd-order self- and cross-Volterra kernels of RF PAs in a 3 × 3 multiple-input multiple-output (MIMO) system. The main block structures of the models are determined by analysing the frequency-domain symmetry properties of the Volterra kernels in different three-dimensional (3D) frequency spaces. This approach significantly simplifies the structure of the 3rd-order non-linear MIMO model.

    The following parts of the thesis investigate techniques for behavioural modelling and linearising RF PAs. A piece-wise modelling technique is proposed to characterise the dynamic behaviour and to mitigate the impairments of non-linear RF PAs at different operating points (regions). A set of thresholds decompose the input signal into several sub-signals that drive the RF PAs at different operating points. At each operating point, the PAs are modelled by one sub-model, and hence, the complete model consists of several sub-models. The proposed technique reduces the model errors compared to conventional piece-wise modelling techniques.

    A block structure modelling technique is proposed for RF PAs in a MIMO system based on the results of the three-tone characterisation technique. The main structures of the 3rd- and higher-order systems are formulated based on the frequency dependence of each block. Hence, the model can describe more relevant interconnections between the inputs and outputs than conventional polynomial-type models.

    This thesis studies the behavioural modelling and compensation techniques in both the time and the frequency domains for RF PAs in a 3 × 3MIMO system. The 3D time-domain technique is an extension of conventional 2D generalised memory polynomial (GMP) techniques. To reduce the computational complexity, a frequency-domain technique is proposed that is efficient and feasible for systems with long memory effects. In this technique, the parameters of the model are estimated within narrow sub-bands. Each sub-band requires only a few parameters, and hence the size of the model for each sub-band is reduced.

  • 148.
    Alizadeh, Mahmoud
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. Royal Institute of Technology, Stockholm, Sweden.
    Amin, Shoaib
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. Royal Institute of Technology, Stockholm, Sweden.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Measurement and analysis of frequency-domain Volterra kernels of nonlinear dynamic 3x3 MIMO systems2017In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 66, no 7, p. 1893-1905Article in journal (Refereed)
    Abstract [en]

    Multiple-input multiple-output (MIMO) frequency-domain Volterra kernels of nonlinear order 3 are experimentally determined in bandwidth-limited frequency regions. How the effect of higher nonlinear orders can be reduced and how this affects the estimated errors are discussed. The magnitude and phase of the kernels areKramers-Kronig consistent. The self- and cross-kernels have different symmetries and the kernels are therefore determined and analyzed in different regions in the 3D frequency space. By analyzing the properties along certain paths in the 3D frequency space, the block structures for the respective kernels are determined. These block structures contain the significant blocks of the general block structures for third-order kernels. The device under test is a MIMO transmitter for radio frequency signals.

  • 149.
    Alizadeh, Mahmoud
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. KTH, Teknisk informationsvetenskap.
    Händel, Peter
    KTH, Teknisk informationsvetenskap.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Basis Function Decomposition Approach in Piece-Wise Modeling for RF Power Amplifiers2018In: 6th Telecommunications forum TELFOR 2018, Belgrade: Telecommunications society , 2018Conference paper (Refereed)
    Abstract [en]

    In this paper, a new approach is proposed to decompose the basis functions in a piece-wise modeling technique for nonlinear radio frequency (RF) power amplifiers. The proposed technique treats the discontinuity problem of the model output at the joint points between different operating points, whereas preserves the linear and nonlinear properties of the original model within each region. Experimental results show that the proposed technique outperforms the conventional piece-wise model in terms of model errors.

  • 150.
    Alizadeh, Mahmoud
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electrical Engineering, Mathematics and Science, Electronics. KTH, Teknisk informationsvetenskap.
    Händel, Peter
    KTH, Teknisk informationsvetenskap.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electrical Engineering, Mathematics and Science, Electronics.
    Behavioral modeling and digital pre-distortion techniques for RF PAs in a 3 × 3 MIMO system2019In: International journal of microwave and wireless technologies, ISSN 1759-0795, E-ISSN 1759-0787Article in journal (Refereed)
    Abstract [en]

    Modern telecommunications are moving towards (massive) multi-input multi-output systems in 5th generation (5G) technology, increasing the dimensionality of the system dramatically. In this paper, the impairments of radio frequency (RF)power amplifiers (PAs) in a 3x3 MIMO system are compensated in both time and frequency domains. A three-dimensional(3D) time-domain memory polynomial-type model is proposed as an extension of conventional 2D models. Furthermore, a 3D frequency-domain technique is formulated based on the proposed time-domain model to reduce the dimensionality of the model, while preserving the performance in terms of model errors. In the 3D frequency-domain technique, the bandwidth of a system is split into several narrow sub-bands, and the parameters of the system are estimated for each subband. This approach requires less computational complexity, and also the procedure of the parameters estimation for each sub-band can be implemented independently. The device-under-test (DUT) consists of three RF PAs including input and output cross-talk channels. The proposed techniques are evaluated in both behavioural modelling and digital pre-distortion(DPD) perspectives. The results show that the proposed DPD technique can compensate the errors of non-linearity and memory effects by about 23.5 dB and 7 dB in terms of the normalized mean square error and adjacent channel leakage ratio, respectively.

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