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  • 1.
    Tilander, Åke
    Högskolan i Gävle, Institutionen för humaniora och samhällsvetenskap, Ämnesavdelningen för religionsvetenskap.
    A Theme in C. G. Jung's Psychohistory: an Analysis of the Origin and Development of a Complex1990Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 2.
    Söderlund, Maud
    Högskolan i Gävle, Institutionen för pedagogik, didaktik och psykologi.
    God omvårdnad. En beskrivning av intentioner och uppfattningar.1993Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    I den svenska lagstiftningen (Hälso- och sjukvårdslagen, 1983, 1985) som reglerar hälso- och sjukvårdens verksamhet framhålls humanistiska värderingar. Den vårdideologi som gäller i Sverige är att kunna vårda utifrån en helhetssyn. Sjuksköterskorna som ansvariga för omvårdnad anses behöva förändra sina kunskaper, attityder och värderingar för att detta ska kunna ske (Socialstyrelsens författningssamnling, SOSFS, 1990:15). Detta kan beskrivas som en konflikt mellan hur omvårdnad anses vara och hur den borde vara. Studiens problem tar sin utgångspunkt i yrkesutbildning till sjuksköterska och de påverkansprocesser, i form av uppfattningar av omvårdnad, som möter de studerande i denna konflikt. I den teoretiska utbildningen möts de studerande av omvårdnad som ett vetenskapligt ämne och beskrivs bl a i teorier om hur omvårdnad bör vara. I den praktiska utbildningen handleds studerande av sjuksköterskor in i en yrkesroll som sjuksköterska. Dessa sjuksköterskor har varierande erfarenheter av omvårdnad. Om omvårdnad som den är bl a bestäms av sjuksköterskors uppfattningar måste dessa beskrivas. Hur uppfattningar av omvårdnad "borde vara" och hur omvårdnad "uppfattas vara" är relaterade till varandra och blir viktiga att synliggöra.

    Denna undersökning är till sin karaktär deskriptiv. Utgångspunkten för studien är induktiv. Materialet för denna kartläggning har insamlats på olika sätt genom intervjuer, granskning av offentliga dokument som i Sverige reglerar sjuksköterskors ansvarsområde, litteratur med relevans för omvårdnadsutvecklingen i Sverige samt vad fyra omvårdnadsteoretiker över tre decennier beskriver som god vård. Materialet har utifrån ett fenomenograftiskt perspektiv (Marton, 1978, 1981, 1990) analyserats med avseende på vilka kvalitativt skilda uppfattningar det ger uttryck för:

    God omvårdnad är något som enbart sjuksköterskor kan ansvara för

    God omvårdnad är ett gemensamt ansvar

    God omvårdnad är att möjliggöra patientens eget ansvar

    Resultatet kan förändra förståelse för omvårdnad som fenomen och utgöra underlag för reflektion och diskussion och möjliggör därmed utveckling av omvårdnad.

  • 3.
    Bustad, Johnny
    Högskolan i Gävle, Institutionen för matematik, natur- och datavetenskap. Natur.
    Shake-up studies of model systems for adsorbates: Department of Quantum Chemistry, Uppsala University1993Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Shake-up studies of model systems for adsorbates are presented. The molecule CO adsorbed on transition metal surfaces belong to one of the most studied systems in surface science. The interest is motivated by fundamental questions about the adsorbate-substrate interaction as well as technical applications, such as catalysis. A good starting point in order to get more detailed understanding of the CO-metal interaction is to study the transition metal carbonyls, where CO is coordinated to metal atoms. It has been found that many aspects of the adsorbate systems can be modelled by these molecules. These are the main reasons for studying the molecules Mo(CO)6 and Cr(CO)6, for which results are reported in this thesis.

  • 4.
    Söderlund, Maud
    Högskolan i Gävle, Institutionen för pedagogik, didaktik och psykologi.
    Uppfattningar av god omvårdnad: - en fenomenografisk studie1993Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    I den svenska lagstiftningen (Hälso- och sjukvårdslagen, 1983, 1985) som reglerar hälso- och sjukvårdens verksamhet framhålls humanistiska värderingar. Den vårdideologi som gäller i Sverige är att kunna vårda utifrån en helhetssyn. Sjuksköterskorna som ansvariga för omvårdnad, dvs. "nursing", anses behöva förändra sina kunskaper, attityder och värderingar för att detta ska kunna ske (Socialstyrelsens författningssamnling, SOSFS, 1990:15). Detta kan beskrivas som en konflikt mellan hur omvårdnad anses vara och hur den borde vara. Om omvårdnad som den är bestäms av sjuksköterskors uppfattningar måste dessa beskrivas. Uppfattaningar som kan identifieras som den "outtalade grunden" (Marton, 1978, 1981, 1990) för våra attityder, värderingar och handlingar och kan identifieras i allt som uttrycker människors tankeprocesser, från språk till skrift eller handling.

    Denna undersökning är till sin karaktär deskriptiv. Utgångspunkten för studien är induktiv. Materialet för denna kartläggning har insamlats på olika sätt genom intervjuer, granskning av offentliga dokument som i Sverige reglerar sjuksköterskors ansvarsområde, litteratur med relevans för omvårdnadsutvecklingen i Sverige samt vad fyra omvårdnadsteoretiker över tre decennier beskriver som god vård. Materialet har utifrån ett fenomenograftiskt perspektiv analyserats med avseende på vilka kvalitativt skilda uppfattningar det ger uttryck för:

    God omvårdnad är något som enbart sjuksköterskor kan ansvara för

    God omvårdnad är ett gemensamt ansvar

    God omvårdnad är att möjliggöra patientens eget ansvar

    Resultatet speglas mot ett i Sverige officiellt ställningstagande för vad god omvårdnad borde vara mot en autonom vårdvetenskaps teoretiska referensram (Eriksson, 1991), dvs. "caring", som gestalt mot gestalt.

    Kunskapsintresset är att försöka tydliggöra och benämna sjuksköterskors erfarenheter av vård och därigenom förändra förståelse för god omvårdnad som fenomen. Förhoppningsvis kan detta utgöra underlag för reflektion och diskussion för att möjliggöra en utveckling av svensk vård och omvårdnad.

  • 5.
    Nylén, Karl-Olof
    Högskolan i Gävle, Institutionen för teknik och byggd miljö. Industriell ekonomi.
    Cost of failure in a major civil engineering project1996Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 6.
    Westin, Ingrid
    Uppsala universitet, Engelska institutionen.
    The language of English newspaper editorials from a 20th-century perspective1997Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 7.
    Ekstrand, Eva
    Umeå universitet.
    Någon sa att jag borde skriva: om yrkesidentitet i nio kvinnliga journalisters berättelser1998Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This study concerns nine female journalists and their creation of their professional identity. Their stories have been written down in cooperation with the interviewer and interpreted hermeneutically (Ricoeur). The journalists position in the mass media organization is paradoxical. They are expected to act as defenders of democracy and free speech, but also to obey the "laws" of the mass media organization, such as efficiency and rationality. The thesis is that the paradoxical situation has impact on the creating of the journalists identity, often described in stereotypes such as the Pedagogue, the Storyteller etcetera. The narrative in the stories is contructed with the following elements: the step - into the profession, the confirmation and the repayment. When the journaliss take the step it turns out that everybody, except one, introduces a helper into the story: someone else told them to take the step. This can be interpreted in at least two ways; the helper takes the initiative and thereby reduces the self in the narrative, or he/she helps the journalist not to identify with a rational goaloriented (male) subject who selfconciously chooses journalism in order to changing the world, or at least save democracy, thus providing a possibility to creating another professional identity. The journalists are well acknowledged on their jobs, but the relation to the public is somewhat complicated. Finally a tentative attempt is made to find a concept that may capture their professional identities. The proposed concept is a "post-modern journalist identity", of which point of departure is not the modernist instrumental stereotypes, but the individuals constant creation of being a subject in their own stories, regardless of idols, class or gender.

  • 8.
    Andersson, Mikael
    Högskolan i Gävle, Institutionen för teknik och byggd miljö. Industriell ekonomi.
    Discrete Event Operational Simulation in the Manufacturing System1999Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 9.
    Ryner, Birgitta
    Högskolan i Gävle, Institutionen för pedagogik, didaktik och psykologi. Didaktik.
    Skolans musik - tolkad genom lärarstuderandes minnesbilder1999Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 10.
    Westergren, Karl-Erik
    Högskolan i Gävle, Institutionen för matematik, natur- och datavetenskap. Matematik och statistik.
    Estimation of energy need for heating in single-family houses: A dissertation for the technology licentiate´s degree in statistics2000Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 11.
    Ljungström, Martin
    Högskolan i Gävle, Institutionen för teknik och byggd miljö. Industriell ekonomi.
    Obstacles Towards a Work-Development-Oriented TQM-strategy2000Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 12.
    Blomqvist, Claes
    Högskolan i Gävle, Institutionen för teknik och byggd miljö. Inomhusmiljö.
    Okonventionell tillförsel av ventilationsluft2000Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 13.
    Fransson, Göran
    Högskolan i Gävle, Institutionen för pedagogik, didaktik och psykologi. Avdelningen i didaktik.
    Att stödja flygförares utveckling – en studie av instruktörsbeteenden under övning i flygsimulator.2001Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Föreliggande licentiatuppsats utgör en kappa som bygger två rapporter. Dessa rapporter, ”Utbildning under uppbyggnad” (Fransson m.fl, 1999a) samt ”Lära av egen kraft” (Fransson m.fl, 1999b) har producerats som ett led i en utvärdering av en av svenska flygvapnets pilotutbildningar.

    Syftet med uppsatsen är att ge en översiktlig bild av de överväganden, utgångspunkter och analyser som präglat dessa; att diskutera några av resultaten i ett vidgat teoretiskt perspektiv, i detta fall ett institutionellt perspektiv, samt att diskutera metodernas och teoriernas lämplighet i sammanhanget. De resultat som diskuteras har avgränsats till att beröra exemplet om två instruktörers pedagogiska beteendemönster under en övning i en simulator.

    De som förenar de båda bakomliggande rapporterna är det sociokulturella perspektiv de båda utgår ifrån, den etnografiskt inspirerade datainsamlings- och analysmetodiken samt att de bygger på studier i samma utbildningsmiljö. I den första rapporten analyseras empiriska data med hjälp av aktivitetsteori. Som modell för arbetsgången tillämpades metodiken inom den utvecklingsinriktade arbetsforskningen, ”developmental work research”. I den andra rapporten analyseras förutsättningar för lärande genom att betrakta lärande i perspektivet av ett legitimt perifert lärande.

    I uppsatsen förs diskussioner bl.a. om att begreppet motsättning, som ingår i den aktivitetsteoretiska begreppsapparaten, effektivt kan bidraga till att fokusera på faktorer eller förhållanden i verksamheten som utveckling och förändring kan utgå ifrån. Motsvarande tydlighet finns inte uttalad inom det institutionella perspektivets begreppsapparat. Vidare konstateras att det finns vissa svårigheter att problematisera relationen mellan det aktivitetsteoretiska perspektivet och det institutionellt perspektivet. En av orsakerna därtill är att institutionsbegreppet i samband med aktivitetsteoretiska analyser förefaller tillämpas utan närmare definition. Utförligare beskrivningar av hur institutionsbegreppet förstås och används förordas för att kunna göra närmare analyser av hur de båda perspektiven kompletterar varandra.

    I uppsatsen framhålls den etnografiska metodens tillämpbarhet. En svårighet som kan uppstå när man genomför studier i högteknologiska miljöer påtalas dock. En risk kan finnas att forskaren inledningsvis fascineras av tekniska aspekter, med följd att fokus på de mänskliga aspekterna då fördunklas. Denna effekt bör inte underskattas av forskare.

  • 14.
    Pettersson, Carina
    Högskolan i Gävle, Institutionen för matematik, natur- och datavetenskap. Datavetenskap.
    Datorer åt många: en studie om datorn som vardagsteknik och kunskapsverktyg2001Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 15.
    Sammalisto, Kaisu
    Högskolan i Gävle, Institutionen för teknik och byggd miljö, Ämnesavdelningen för industriell ekonomi. Lund University, Lund, Sweden.
    Developing TQEM in SMEs: Management System Approach2001Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 16.
    Sammalisto, Kaisu
    Högskolan i Gävle, Institutionen för teknik och byggd miljö. Industriell ekonomi.
    Developing TQEM in SMEs. Management Systems Approach2001Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 17.
    Wijk, Katarina
    Högskolan i Gävle, Institutionen för pedagogik, didaktik och psykologi, Ämnesavdelningen för pedagogik.
    Constructing Risk-Taking Youth: Extrapolating Theories of Health Education and Constructed Determinants of Risk-Taking among Youth in Preventive Sexual Health Education Interventions2002Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 18.
    Niss, Camilla
    Högskolan i Gävle, Institutionen för teknik och byggd miljö. Industriell ekonomi.
    Knowledge Brokering Across the Boundaries of Organisations: An Interactionist Interpretation of a Temporary ´Mirror-organisation´2002Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 19.
    Marteinsson, Björn
    Högskolan i Gävle, Institutionen för teknik och byggd miljö. Byggnadskvalitet.
    Assessment of Service Lives in the Design of Buildings: Development of the Factor Method2003Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 20.
    Lindgren, John
    Högskolan i Gävle, Institutionen för teknik och byggd miljö. Industriell ekonomi.
    Logistikens aktörer2003Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 21.
    Dabhilkar, Mandar
    Högskolan i Gävle, Institutionen för teknik och byggd miljö. Industriell ekonomi.
    Mot en balanserad styrning i teambaserade organisationer2003Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 22.
    Wisell, David
    Högskolan i Gävle, Institutionen för teknik och byggd miljö. Elektronik.
    A Baseband Time Domain Measurement System for Dynamic Characterisation of Power Amplifiers with High Dynamic Range over Large Bandwidth2004Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 23.
    Isaksson, Magnus
    Högskolan i Gävle, Institutionen för teknik och byggd miljö, Ämnesavdelningen för elektronik.
    Behavioural Modelling of Radio Frequency Power Amplifiers: An Evaluation of Some Block Structure and Neural Network Models2005Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This work considers behavioral modelling of radio frequency power amplifiers. Due to the use of modern digital modulation methods power amplifiers are nowadays subjected to signals having a considerable bandwidth and a fast changing envelope. This means that traditional quasi-memoryless amplitude-to-amplitude (AM/AM) and amplitude-to-phase (AM/PM) characteristics are no longer enough to describe and model the behavior of power amplifiers, neither can they be successfully used for linearization.

    In this thesis, sampled input and output data are used for identification and validation of some block structure models with memory. The time-discrete Volterra model, the Wiener model, the Hammerstein model, and the radial-basis function neural network are all identified and compared with respect to in-band and out-of-band errors. Two different signal types, i.e. multi tones and noise, with different powers, peak-to-average ratios, and bandwidths have been used as input to the amplifier. Two different power amplifiers were investigated, one designed for the third generation mobile telecommunication systems and one for the second generation.

    A stepped three-tone measurement technique based on digitally modulated baseband signals is presented. The third-order Volterra kernel were determined from identified inter-modulation products. The properties of the Volterra kernel along certain parts in the three dimensional frequency space were analysed and compared to the Wiener and Hammerstein models.

  • 24.
    Hallberg, Daniel
    Högskolan i Gävle, Institutionen för teknik och byggd miljö, Ämnesavdelningen för byggnadskvalitet.
    Development and Adaptation of a Life Cycle Management System for Constructed Works2005Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Lifetime Engineering (or Life Cycle Engineering) is a technical approach for meeting the

    current objective of sustainable development. The approach is aimed to turn today’s reactive

    and short-term design, management and maintenance planning towards an optimised and

    long-term technical approach. The life cycle based management and maintenance planning

    approach includes condition assessment, predictive modelling of performance changes,

    maintenance, repair and refurbishment planning and decisions. The Life Cycle Management

    System (LMS) is a predictive and generic life cycle based management system aimed to

    support all types of decision making and planning of optimal maintenance, repair and

    refurbishment activities of any constructed works. The system takes into account a number of

    aspects in sustainable and conscious development such as human requirements, life cycle

    economy, life cycle ecology and cultural requirements. The LMS is a system by which the

    complete system or parts thereof, works in co-operation or as a complement to existing

    business support systems. The system is module based where each module represents a subprocess

    within the maintenance management process. The scope of this thesis is focused on

    development and adaptation of the predictive characteristic of LMS towards a presumptive

    user. The objective is to develop and adapt a Service Life Performance Analysis module

    applicable for condition based Facility Management System in general and for condition

    based Bridge Management System in particular. Emphasis is placed on development and

    adaptation of a conditional probability based Service Life Performance Analysis model in

    which degradation models and Markov chains play a decisive role. The thesis deals also with

    development and adaptation of environmental exposure data recording and processing, with

    special emphasis on quantitative environmental classification in order to provide a simplified

    method of Service Life Performance Analysis.

  • 25.
    Strömberg, Annika
    Högskolan i Gävle, Institutionen för ekonomi, Ämnesavdelningen för företagsekonomi.
    Förmågor i samverkan: byggherrekompetens ur ett processperspektiv2005Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 26.
    Jerlinder, Kajsa
    Högskolan i Gävle, Institutionen för pedagogik, didaktik och psykologi, Ämnesavdelningen för pedagogik.
    Rättvis idrottsundervisning för elever med rörelsehinder: dilemma kring omfördelning och erkännande.2005Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 27.
    Bellander, Rickard
    Högskolan i Gävle, Institutionen för teknik och byggd miljö, Ämnesavdelningen för byggnadskvalitet.
    Testing large samples of PCM in water calorimeter and PCM used in room applications by night-air cooling2005Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

     

    The latent-heat-storage capacity in Phase-Change Materials can be used for storing or releasing energy within a small temperature interval. Upon the phase transition taking place in a narrow temperature span, the material takes up or releases more energy compared to sensible heat storage. For an ideal phase-change material, the transition temperature is a single value, but for the most common phase-change materials on the market, used in building applications, the transition temperature is distributed within a temperature range of several degrees.

    Integration of phase-change materials in building applications can be effected in several ways, for example by impregnating phase-change materials into porous building materials like concrete, wallboards, bricks or complements of the building structure. Integrating storages filled with phase-change materials makes other implementations, for instance accumulating tanks or envelopes as presented in this thesis, in an air heat exchanger. An appropriate phasetransition temperature of the supposed application is critical to the functionality of the material. For example, in cooling applications, the transition temperature of the material should be a few degrees lower than the requested comfort temperature in the building, and the opposite for heating applications.

    In order to assess the thermal properties and the durability of the material, a watercalorimetric equipment was developed and employed in an accelerated testing programme. The heat capacity of the material and in particular possible change in the heat capacity over time, after thermal cycling of the material, were measured. In the thermal cycling of the material from solid to liquid phase, the temperature rise and required energy supply were recorded. The testing programme was undertaken according to control procedures and documents. In order to be able to utilize the heat-storage capacity in the best way, it is necessary to gain knowledge about thermal properties of the material, especially the long-term behaviour of the material and the deterioration rates of the thermal properties.

    A semi-full-scale air heat exchanger based on phase-change material was developed and tested under real temperature conditions during the summer of 2004. The test results were used to compare and verify computer simulations made on a similar plant. The air heat exchanger utilises the ambient diurnal temperature swing to charge and discharge the phasechange material. The material tested in the calorimeter and in the air heat exchanger has an estimated phase-change temperature of about 24 °C.

  • 28.
    Chilo, José
    Högskolan i Gävle, Institutionen för teknik och byggd miljö, Ämnesavdelningen för elektronik.
    Filtering extracting features from infrasound data2006Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

     

    The goal of the research presented in this thesis is to extract features, to filter and get fingerprints from signals detected by infrasound, seismic and magnetic sensors. If this can be achieved in a real time system, then signals from various events can be detected and identified in an otherwise torrent data.

    Several approaches have been analyzed. Wavelet transform methods are used together with ampligram and time scale spectrum to analyze infrasound, seismic and magnetic data. The energy distribution in the frequency domain may be seen in wavelet scalograms. A scalogram displays the wavelet coefficients as a function of the time scale and of the elapsed time. The ampligram is a useful method of presentation of the physical properties of the time series. The ampligram demonstrate the amplitude and phase of components of the signal corresponding to different spectral densities. The ampligram may be considered as an analogy to signal decomposition into Fourier components. In that case different components correspond to different frequencies. In the present case different components correspond to different wavelet coefficient magnitudes, being equivalent to spectral densities. The time scale spectrum is a forward wavelet transform of each row (wavelet coefficient magnitude) in the ampligram. The time scale spectrum reveals individual signal components and indicates the statistical properties of each component: deterministic or stochastic.

    Next step is to distinguish between different sources of infrasound on-line. This will require signal classification after detection is made. The implementation of wavelet – neural network in hardware may be a first choice. In this work the Independent Component Analysis is presented to improve the quality of the infrasonic signals by removing background noise before the hardware classification. The implementation of the discrete wavelet transform in a Field Programmable Gate Array (FPGA) is also included in this thesis using Xilinx System Generator and Simulink software.

    A study of using infrasound recordings together with a miniature 3-axis fluxgate magnetometer to find meteorites as soon as possible after hitting the earth is also presented in this work.

  • 29.
    Bengtsson, Olof
    Högskolan i Gävle, Institutionen för teknik och byggd miljö, Ämnesavdelningen för elektronik.
    Integration and Analysis of RF-Power LDMOS Transistors2006Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
  • 30.
    Stjernström, Susanne
    Högskolan i Gävle, Institutionen för teknik och byggd miljö, Ämnesavdelningen för industriell ekonomi.
    Knowledge creation in collaborative product development2006Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 31.
    Sundgren, David
    Högskolan i Gävle, Institutionen för matematik, natur- och datavetenskap, Ämnesavdelningen för matematik och statistik.
    Distribution of expected utility in second-order decision analysis2007Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In decision analysis maximising the expected utility is an often used approach in choosing the optimal alternative. But when probabilities and utilities are vague or imprecise expected utility is fraught with complications. Studying second-order effects on decision analysis casts light on the importance of the structure of decision problems, pointing out some pitfalls in decision making and suggesting an easy to implement and easy to understand method of comparing decision alternatives. The topic of this thesis is such second-order effects of decision analysis, particularly with regards to expected utility and interval-bound probabilities. Explicit expressions for the second-order distributions inherent in interval-bound probabilities in general and likewise for distributions of expected utility for small decision problems are produced. By investigating these distributions the phenomenon of warping, that is concentration of belief, is studied.

  • 32.
    von Haartman, Robin
    Högskolan i Gävle, Institutionen för teknik och byggd miljö, Ämnesavdelningen för industriell ekonomi.
    External integration and the need for manufacturing competence2007Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    For a number of years, manufacturers have increasingly focused on their perceived core competencies and outsourced activities not seen as such. In doing so there are an increasing number of competencies that fall outside the ‘core’ domain but are nonetheless required for effective product and process development. The proposed solution to this problem has been external integration with an emphasis on collaborative product or process development and also the wider concept of supply chain management. It is, however, not always easy to substitute internal competencies with customers’ and suppliers’ capabilities. Many authors have focused on finding the prerequisites for effective external integration and particularly on areas such as trust and power.

    This thesis contributes to the literature by extending the concept of absorptive capacity into the manufacturing domain and in the context of external integration. A conceptual framework is developed, where different streams of the literature have been merged into one coherent model. Integral parts of this framework are the concept of absorptive capacity as well as a model of competitive priorities. Competitive priorities have been taken into account as firms differ; what contributes to competitive advantage for one firm may be irrelevant for another.

    Three papers are included in the thesis. The first one uses survey data, from a representative sample of the Swedish manufacturing industry, in order to validate the concept of absorptive capacity in the manufacturing sector. The second paper also uses survey data but aims to shed some light on competitive priorities’ impact on both the extent and the outcome of internal and external integration. The third paper describes a case study of a first-tier supplier and aims to illustrate how absorptive capacity in a manufacturing firm may look in practice.

    The thesis concludes that the conceptual framework is indeed useful for understanding the challenges of effective external integration. Internal manufacturing competencies may allow a firm to integrate more effectively external sources, but the required competencies may vary from firm to firm. This implies a need for a fit between companies’ competitive priorities, external integration and absorptive capacity. It also implies that companies may struggle to achieve competitive advantage by utilising their customers and suppliers if they do not simultaneously develop appropriate competencies in-house.

  • 33.
    Stojanovic, Bojan
    Högskolan i Gävle, Institutionen för teknik och byggd miljö, Ämnesavdelningen för byggnadskvalitet.
    Life performance assessment methodologies for combined solar energy technologies: a case study on system parts in Nordic climates2007Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The main questions concerning energy technologies today are their economical and environmental impacts. These entities are (at the present) assessed on the basis that operations proceed as newly installed/designed systems, during an assumed working life period. While this is the common way of perceiving energy systems, performance-over-time will change as an effect of (e.g. material) degradation and not solely of different operation scenarios. How and to what extent, is the question that needs assessing in order to evaluate if these changes will jeopardise the intended system performance requirement. In turn, this pro-active assessment and analysis is in line with today’s performance based directives, laws, regulations and concepts; of which the working life is an essential part. The main context of the thesis, is a contribution to the R&D topic on life performance of energy technologies, with papers on a literature review and case study on two system parts: solar collector and ground heat exchanger (borehole); within the energy technology area of combined solar energy technologies/systems utilised in buildings. The thesis specifically presents a general description of requirements on constructed works and their material, components and systems. It also gives an insight to the energy technology R&D and engineering sector, regarding durability and service life assessment methodologies; and also to the durability of constructed works sector, regarding the needs for assessing material degradation in relation to system performance. The case studies presented in the thesis, show how durability of energy technologies may be sought-after, as well as specific knowledge and useful tools, methodologies and test setups for assessing long-term performance of combined solar energy technologies (in this case a solar-assisted heat pump system utilising a building integrated Unglazed Solar Collector and energy storage). The utilisation of solar collectors and heat pumps (primarily for space and domestic tap water heating) has rapidly increased in Sweden during the last decades. Sweden has today the largest heat pump market in Europe. During recent years, there has also been an increased interest in heating systems that combine heat pumps with solar collectors (glazed and unglazed) and energy storages; with the aim of attaining a system that provides higher energy and greater economical performances than individual solar collector or heat pump systems. If these systems are to be successful they must be economically feasible; placing emphasis on the cost, durability and performance of the system. The main issue on life performance of energy technologies is how and to what extent, performance reduction in individual materials and components influences the overall system performance; as the essence of energy system sustainability is system performance.

  • 34.
    Boustedt, Jonas
    Högskolan i Gävle, Institutionen för matematik, natur- och datavetenskap, Ämnesavdelningen för datavetenskap.
    Students working with a large software system: experiences and understandings2007Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This monograph describes an empirical study with the overall aim of producing insights about how students experience the subject Computer Science and its learning environments, particularly programming and software engineering.

    The research takes a start in the students' world, from their perspective, using their stories, and hence, we have chosen a phenomenographic approach for our research. By interpreting the students' descriptions and experiences of various phenomena and situations, it is possible to gain knowledge about which different conceptions students can have and how teaching and the learning environment affect their understanding. In this study, we focus specifically on students' conceptions of aspects of object-oriented programming and their experiences of problem solving situations in connection with object-oriented system development.

    The questions posed enlighten and focus on the students' conceptions of both tangible and abstract concepts; the study investigates how students experienced a task concerning development in a specific software system, how they conceived the system itself, and how the students describe the system's plugin modules. Academic education in programming deals with abstract concepts, such as interfaces in the programming language Java. Hence, one of the questions in this study is how students describe that specific abstract concept, in a context where they are conducting a realistic software engineering task.

    The results show that there is a distinct variation of descriptions, spanning from a concrete to-do list, to a more advanced description where the interface plays a crucial role in order to produce dynamic and adaptive systems. The discussion interprets the results and suggests how we can use them in teaching to provide an extended and varied understanding, where the educational goal is to provide for and strengthen the conditions for students to be able to learn how to develop and understand advanced software.

  • 35.
    Larsson, Johan
    Mittuniversitetet, Institutionen för teknik, fysik och matematik.
    The effect of leadership values, behaviors and methologies on quality and health2007Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Syftet med den forskning som presenteras i denna avhandling är att bidra till ökad kunskap om hur ledarskap kan praktiseras för att främja både medarbetarnas hälsa och organisationers kvalitetsarbete. Tre forskningsfrågor är ställda: 1.Hur relaterar ledarnas värderingar till ledarnas beteende samt aspekter av hälsa och kvalitet?2.Hur relaterar ledarnas beteende till aspekter av hälsa och kvalitet?3.Hur relaterar ledarnas arbetssätt till aspekter av hälsa och kvalitet?Forskningen baserar sig på två fallstudier. Fallstudie I berör tre framgångsrika arbetsplatser som fått utmärkelsen Sveriges bästa arbetsplats. Fokus i denna fallstudie är huvudsakligen på de arbetssätt som används. Fallstudie II avser åtta arbetsplatser i Jämtland och det är särskilt värderingar, beteenden och arbetssätt som har studerats. Rörande ledarskap är Teori X och Teori Y använd som teoribas för att studera ledarnas värderingar. Den tredimensionella ledarbeteendeteorin (förändring, uppgift, relation) är använd när ledarnas beteende mäts och diskuteras. Både kvalitativa och kvantitativa metoder är använda i forskningen. Ledare med X-inriktning på ledarvärderingarna har lägre resultat när medarbetarna värderar organisationens kvalitetsaspekter och samtliga tre dimensioner rörande ledarbeteendet. Vissa indikationer finns att organisationer med Y-orienterade ledare har medarbetare med bättre hälsa. Den ledarskapsprofil som har de bästa resultaten rörande kvalitetsaspekter och hälsoutfall har höga värden på alla tre dimensioner med högsta värdet på relation, följt av förändring på liknande nivå samt även uppgiftsorienteringen hög men lägre än de andra två dimensionerna. Gemen-samma arbetssätt hos framgångsrika organisationer har identifierats och presenterats. Mönster mellan framgångsrika organisationer i studie I och II har identifierats.

  • 36.
    Elm, Annika
    Högskolan i Gävle, Institutionen för pedagogik, didaktik och psykologi, Ämnesavdelningen för didaktik.
    Interaktion och naturvetenskap i en förskola och en förskoleklass2008Licentiatavhandling, monografi (Övrigt vetenskapligt)
  • 37.
    Hadrevi, Jenny
    Högskolan i Gävle, Centrum för belastningsskadeforskning.
    Human Skeletal Muscle: a basic proteomic approach2009Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The trapezius is a muscle of clinical interest due to its susceptibility to chronic work related musculoslteletal disorders. The mechanisms underlying these conditions are not fully understood. A comprehensive and comparative biochemical characterization of the trapezius muscle may reveal particular individual traits that make it more susceptible to chronic work related musculoskeletal disorders. We have examined the suitability and outcome of a proteomic method, two-dimensional difference gel electrophoresis (2D-DIGE), in the analysis of human skeletal muscle. This method allows a simultaneous comparison of large numbers of proteins within a limited pH and molecular weight range. A protocol using the 2D-DIGE method was adapted to human muscle and its repeatability was tested on human vastus lateralis muscle samples from one healthy male donor. The vastus lateralis is the most well studied muscle in the human body and was therefore used as the gold standard. The method was validated using western blot technique. Subsequently, a comparative 2D-DIGE analysis using the validated protocol was conducted on vastus lateralis and trapezius muscle biopsies from five healthy male subjects. Proteins were identified using matrix assisted laser desorption ionisation time of flight (MALDI-TOF) mass spectrometry and immunohistochemistry was performed on serial sections to confirm the findings. The 2D-DIGE method proved to be a good screening tool to further detect biochemical differences between muscles. The comparative study between the trapezius and vastus lateralis demonstrated significant differences in 25 important metabolic and structural proteins. In particular, it showed differences in proteins related to oxidative stress, which may be of specific importance for the susceptibility of the trapezius muscle to work related musculoskeletal disorders. These results provide a baseline for future studies on the trapezius muscle and puts further emphasis on the differences between different types of skeletal muscle.

  • 38.
    Löfqvist, Lars
    Högskolan i Gävle, Institutionen för teknik och byggd miljö, Ämnesavdelningen för industriell ekonomi. Högskolan i Gävle, Centrum för logistik och innovativ produktion.
    Innovation and Design Processes in Small Established Companies2009Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis examines innovation and design processes in small established companies. There is a great interest in this area yet paradoxically the area is under-researched, since most innovation research is done on large companies. The research questions are: How do small established companies carry out their innovation and design processes? and How does the context and novelty of the process and product affect the same processes?

    The thesis is built on three research papers that used the research method of multiple case studies of different small established companies. The innovation and design processes found were highly context dependent and were facilitated by committed resources, a creative climate, vision, low family involvement, delegated power and authority, and linkages to external actors such as customers and users. Both experimental cyclical and linear structured design processes were found. The choice of structure is explained by the relative product and process novelty experienced by those developing the product innovation. Linear design processes worked within a low relative novelty situation and cyclical design processes worked no matter the relative novelty. The innovation and design processes found were informal, with a low usage of formal systematic design methods, except in the case of design processes for software. The use of formal systematic methods in small companies seems not always to be efficient, because many of the problems the methods are designed to solve are not present. Customers and users were found to play a large and important role in the innovation and design processes found and gave continuous feedback during the design processes. Innovation processes were found to be intertwined, yielding synergy effects, but it was common that resources were taken from the innovation processes for acute problems that threatened the cash flow. In sum, small established companies have the natural prerequisites to take advantage of lead-user inventions and cyclical design processes. Scarce resources were found to be the main factor hindering innovation, but the examined companies practiced several approaches to increase their resources or use existing scarce resources more efficiently in their innovation and design processes. Examples of these approaches include adopting lead-user inventions and reducing formality in the innovation and design processes.

  • 39.
    Carlsson, Inga-Lill
    Linköpings Universitet.
    Meeting increased logistical demands: Developing as a small- and medium-sized system supplier2009Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
  • 40.
    Landin, Per Niklas
    Högskolan i Gävle, Institutionen för teknik och byggd miljö, Ämnesavdelningen för elektronik.
    On Radio Frequency Behavioral Modeling: Measurement Techniques, Devices and Validation Aspects2009Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Effektförstärkare för radiofrekvensapplikationer utgör fortfarande ett av de största problemen i trådlösa kommunikationssystem. Detta beror på att dessa förstärkare är ickelinjära, har låg energieffektivitet och ger mycket distortioner. Bättre verktyg för att förstå och korrigera dessa beteenden är nödvändiga. Ett sådant verktyg är beteendemodellering. En beteendemodell kanses som en svart låda med insignal(er) och utsignal(er). In detta fall är dessasignaler samplade basbandssignaler och den svarta lådan är en matematisk relation mellan en insignal och en utsignal.

    Avhandlingen behandlar några krav för beteendemodellering av nämnda system genom att presentera metoder för utvärdering och förbättring av modellernas prestanda. Detta åstadkoms genom att betrakta ett frekvensviktat felkriterium.

    Ett högpresterande mätsystem är också nödvändigt för experimenten. Prestandan hos det tillgängliga systemet jämförs med prestandan hos ett allmänt erkänt mätsystem, en s.k. storsignalsnätverksanalysator, genom att betrakta prestandan hos beteendemodellerna som extraheras och validerasmed data från respektive mätsystem. Resultatet visar att det existerande mätsystemet har god prestanda.

    Ett stort problem vid beteendemodellering är att kunna sampla med tillräckligt hög hastighet. Genom att använda Zhu-Franks generaliserade samplingsteorem vid beteendemodellering kan en del av detta problem undvikas. Teoremet medför att man kan sampla med en väsentligt lägre samlingsfrekvens än vad Nyquistteoremet säger. Modeller extraheras och prestandanutvärderas genom att använda kriteriet normalized mean square error (NMSE).

    För stabil prediktion och korrektion av utsignalen måste robustheten hos de använda modellerna verifieras. En sådan studie som berör robustheten mot variationer i lastimpedansen har genomförts. Prestandan på direkta modeller försämras med 7 dB mätt som adjacent channel error power ratio (ACEPR). Prestanda på inversmodellen, implementerad som digital predistortion, försämras med upp till 13 dB mätt som adjacent channel power ratio(ACPR).

  • 41.
    Nader, Charles
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för elektronik, matematik och naturvetenskap.
    Enhancing Radio Frequency System Performance by Digital Signal Processing2010Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In this thesis measurement systems for the purpose of characterization of radio frequency power amplifiers are studied. Methods to increase the speed, accuracy, bandwidth, as well as to reduce the sampling requirements and testing cost are presented. A method intended for signal shaping with respect to peak to-average ratio reduction and its effects-improvements on the radio frequency front-end performance is investigated.

    A time domain measurement system intended for fast and accurate measurements and characterization of radio frequency power amplifiers is discussed. An automated, fast and accurate technique for power and frequency sweep measurements is presented. Multidimensional representation of measured figure of merits is evaluated for its importance on the production-testing phase of power amplifiers.

    A technique to extend the digital bandwidth of a measurement system is discussed. It is based on the Zhu-Frank generalized sampling theorem which decreases the requirements on the sampling rate of the measurement system. Its application for power amplifiers behavioral modeling is discussed and evaluated experimentally.

    A general method for designing multitone for the purpose of out-of-band characterization of nonlinear radio frequency modules using harmonic sampling is presented. It has an application with the validation of power amplifiers behavioral models in their out-of-band frequency spectral support when extracted from undersampled data.

    A method for unfolding the frequency spectrum of undersampled wideband signals is presented. It is of high relevance to state-of-the-art radio frequency measurement systems which capture repetitive waveform based on a sampling rate that violates the Nyquist constraint. The method is presented in a compact form, it eliminates ambiguities caused by folded frequency spectra standing outside the Nyquist band, and is relevant for calibration matters.

    A convex optimization reduction-based method of peaks-to-average ratio of orthogonal frequency division multiplexing signals is presented and experimentally validated for a wireless local area network system. Improvements on the radio frequency power amplifier level are investigated with respect to power added efficiency, output power, in-band and out-of-band errors. The influence of the power distribution in the excitation signal on power amplifier performance was evaluated.

  • 42.
    Wallhagen, Marita
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för bygg- energi- och miljöteknik.
    Environmental Assessment of Buildings and the influence on architectural design2010Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Denna licentiatavhandling behandlar miljöbedömningsmetoder för byggnader. Arbetet bygger på undersökningar analyser, jämförelser och tester av hur miljöbedömningsmetoder bedömer byggnaders miljöprestanda och undersöker även vilka konsekvenser som detta kan ha på arkitektonisk utformning.

    Forskningen börjar med att tre miljöbedömningsmetoder, LEED; Code for Sustainble Homes (CSH) och EcoEffect analyseras och jämförs. Sedan genomfös en fallstudie där de tre metoderna testades på ett bostadshus (ett åttavåningar högt bostadshus i Stockholm). Skillnader gällande miljöbedömningsresultat och miljöbedömningmetodernas förslag på förbättringsåtgärder samt eventuell påverkan på den arkitektoniska utformningen analyseras och diskuteras.

    En av miljöpåverkanskategorierna som bedöms i de tre metoderna, klimatpåverkan orsakad av gaser med inverkan på den globala uppvärmningen, analyseras sedan mer i detalj utifrån ett livscykelperspektiv genom att mäta byggnaders koldioxidekvivalenter (CO2 ekv). Ett förenklat beräkningsverktyg (som här benämns ENSLIC-verktyget), som är baserat på livscykelmetodik, används för att studera en byggnad (ett fyra våningar högt kontorshus i Gävle). Sedan beräknas byggnadens påverkan på CO2 ekv. Effekten av ett flertal föreslagna förbättringsåtgärder på byggnaden samt byte av energikällor analyseras också.

    Studierna visar på miljöbedömningmetodernas komplexitet och presenterar olika sätt att göra jämförelser på. Skillnader och likheter mellan metoderna påvisas, gällande hierarkisk struktur och även på varje hierarkisk nivå, från kategorier till enskilda bedömda frågor och parametrar. Dessa skillnader talar för att olika metoder kan påverka den arkitektoniska utformningen av byggnader.

    Svårigheten i att bedöma komplexa byggnader belyses även när endast en miljöpåverkan bedöms med det LCA baserade ENSLIC-verktyget. Många saker påverkar resultatet, framförallt energianvändning tillsammans med materialanvändning och val av energikällor. Den komplexa och svåra uppgiften att länka samman byggnader med deras miljöpåverkan öppnar upp för användande av interaktiva verktyg som mäter miljöpåverkan som kan användas som beslutshjälpmedel i tidiga designskeden.

  • 43.
    Eklinder Frick, Jens
    Högskolan i Gävle, Akademin för utbildning och ekonomi, Avdelningen för ekonomi, Företagsekonomi. Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Building Bridges and Breaking Bonds: Aspects of social capital in a regional strategic network2011Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Investing in cluster formation or encouraging companies to network in regional strategic networks is a common strategy used by municipalities to promote regional growth in peripheral regions. Previous research has investigated the significance of creating regional advantages by building clusters and regional networks, but researchers have not provided much insight into the problems facing the project management trying to implement such collaboration. In my thesis I describe and analyze a network project in order to shed light upon some of the complications that such a collaboration project might entail. My theoretical framework of analysis rests upon the concept of social capital, a concept that investigates the value that social contacts might incur.

    I have studied a designed network situated in the Swedish municipality of Söderhamn called Firsam. After the closure of the telecommunications factory of Ericsson/Emerson and the military airbase F15 Söderhamn lost 10 % of its local employment in 2004.The need for regional growth programmes therefore became dire. The companies that prior to the closure worked in close collaboration with the Ericsson/Emerson factory were also looking for new revenue streams to compensate for their loss of business. Collaboration with the local manufacturing companies to create innovative projects and to take on joint tenders seemed to be a perfect solution to the problems facing them and the municipality. In this spirit a regional strategic network called Firsam (Företag i regional samverkan) was initiated.

    I analyze the Firsam project using two different aspects of the concept social capital:”bonding” and”bridging”. The bonding form of social capital is associated with small and homogeneous groups that build prerequisites for long-term collaboration by forming close contacts and building trust. The bridging form of social capital creates an open stance towards social relations that enables new contacts to be formed outside one’s own socially established context.

    The bonding form of social capital provides prerequisites for close collaboration but can also result in close-mindedness and over-embeddedness in one’s own social context. Building bridging connections outside one’s own social context might encourage innovative thinking and spur entrepreneurship. The somewhat fleeting connections that are associated with the bridging form of social capital might on the other hand make it difficult to cultivate a common sense of trust within an existing group.

    These different manifestations of social capital create a paradox that might be hard to handle in the design of a regional strategic network. Is it best to support already existing network structures and impose the risk of creating a less innovative environment, or should members from outside the established social context be included in the network design to encourage innovative thinking? There are both positive and negative effects associated with either strategy. I shed light upon this paradox by analyzing the regional strategic network of Firsam.

  • 44.
    Twumasi, Ebenezer
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för bygg- energi- och miljöteknik. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Byggnadsmaterial.
    Molecular filtration: the study of adsorbents2011Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Adsorbent materials for gas purification have been studied and developed for application in many areas. It is known that a single adsorbent may not adequately control multiple contaminants. Therefore, the development of adsorbent materials has accelerated over the past two decades, and is today an area attracting a lot of attention. In view of the global environmental movement for clean air, the development of improved sorbents will help address new challenges that cannot efficiently be met with the generic sorbents that are presently commercially available. On the other hand, the utilization of these new sorbents for specific applications within the area of molecular filtration remains largely unexplored. This thesis presents a synthesis of new sorbent materials, and the characterization and application of these materials for molecular filtration. Commercial adsorbents have been used for benchmarking for the pore properties, the applicability, and the performance of these new adsorbents. A double metal-silica adsorbent has been synthesized. The preparation procedure is based on the use of sodium silicate coagulated with various ratios of magnesium and calcium salts which yields micro-meso porous structures in the resulting material. The results show that molar ratios of Mg/Ca influence the pore parameters as well as the structure and morphology. The bimodal pore size can be tailored by controlling the Mg/Ca ratio. The effect of thermal treatment on pore parameters of these adsorbents has been investigated. The results show that heat treatment had a notable effect on the pore parameters, and that the pore structure was thermally stable even at 600°C.

     A synthesis method has also been developed for the preparation of carbon-silica composites. The method involves a number of routes, which can be summarised as addition of activated carbon particles to (I) the paste, (II) the salt solution, or (III) with the sodium silicate solution. In route II and III the activated carbon is present also before coagulation. The routes presented here leads to carbon-silica composites possessing high micro porosity, meso porosity as well as large surface areas. The increase in micro porosity and surface areas was linear with carbon content. The results shows further that pore size distribution may be tailored based on the route of addition of the carbon particles. Following route I and III a wide pore size (1-30nm) was obtained where as by route II a narrow pore size (1-4nm) was observed. KOH or KMnO4 modified MgCa adsorbent varieties were also prepared. The impregnationwas performed by either a direct synthesis or post-synthesis procedure. Potassium hydroxide and potassium permanganate have been chosen as impregnate chemicals. Results revealed that theimpregnate amount significantly affected both the structural and the gas adsorption characteristics of the impregnated MgCa adsorbents. The properties of double- metal adsorbents, impregnated adsorbents and carbon-silica composites were characterized by various methods (X-ray diffraction, scanning electron microscopy, thermo gravimetric analysis, and nitrogen adsorption at 77K) to study the material structure and morphology, thermal stability, ignition temperature and porous parameters with regard to surface area, pore size, pore size distribution and porosity volume, which is important for optimizing their use in many practical application. The up-take performance of adsorbents for dynamic adsorption of SO2, H2S and toluene was performed in a system similar to the setup usedin ASHRAE 145.1. Finally the applicability and performance of the impregnated modified MgCa-silica adsorbents and composites have been evaluated for H2S, SO2 and toluene adsorption and compared to some commercial adsorbent materials. Results revealed that a potassium permanganate modified MgCa-adsorbent has a H2S adsorption capacity in the range of 0.08-3.19 wt % at 50% efficiency, and that the uptake capacity was relative to the amount of potassiumpermanganate loading. Moreover, KOH modified MgCa-adsorbent shows highest SO2 adsorption capacity (1.7 wt %) which is 3.47 times higher than commercial alumina impregnate with potassium permanganate (0.49 wt %). Carbon-silica composites on the other hand shows adsorption of toluene and high adsorption capacity was obtained when carbon content was 45 wt %. The results further shows that a composite with 45 wt % carbon and obtained via route I present the highest toluene adsorption capacity ( 27.6 wt % relative to carbon content) at 0% efficiency. The large uptake capacity of this composite was attributed to the presence of high microporosity volume and a wide (1-30nm) bimodal pore system consisting of extensive mesopore channels (2-30nm) as well as large surface area. These capacity values of carbon-silica composites are competitive to results obtained for commercial coconut based carbon (31 wt %), and better than commercial alumina-carbon composite.

  • 45.
    Prasad, Sathyaveer
    Högskolan i Gävle, Radio Center Gävle. Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för elektronik, matematik och naturvetenskap.
    Studies of Three Different Methods to Estimate the Up-link Performance of Mobile Phone Antennas2011Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Antennas play an important role in determining the overall radio performance for wireless communications. If all other radio components perform according to their specifications, the performance of a mobile phone can be entirely determined by measuring the efficiency of its antenna. Poor performance of the mobile phone may result in reduced coverage, lower capacity and dissatisfied users. Hence, the ability to accurately and efficiently estimate the radio performance of the mobile phone antenna is of great importance to the telecommunications industry.

    The mobile phone was originally a simple device that only transmitted voice, but it has evolved into a complicated terminal for high data-rate services. This evolution poses many new challenges to mobile phone antenna manufacturers. Antennas must be tested during design and production phases to optimize the in-network radio performance. Standardization bodies, such as the Cellular Telecommunications and Internet Association (CTIA) and the Third Generation Partnership Project (3GPP), have specified procedures for comprehensive testing of the up-link and down-link radio performance of the mobile phone, characterized by the total radiated power (TRP) and total isotropic sensitivity (TIS), respectively.

    In this thesis, three methods for estimating the up-link radio performance of mobile phone antennas are evaluated: the "EMSCAN Lab Express" planar near field system; the "Telia Scattered Field Measurement method"; and the "Bluetest" reverberation chamber. These methods are compared to the reference CTIA- and 3GPP-approved anechoic chamber methods. Each method is experimentally evaluated by measuring the TRP from a number of commercially available mobile phones and comparing the measurements to the results from a standard reference system. The comparison is performed statistically using simple regression analysis. For the reverberation chamber, the analysis is extended by using simple physical and statistical modeling. In particular, a maximum likelihood (ML) estimator for the Rician K factor is derived, statistically and experimentally evaluated.

    Based on the results of this thesis, it can be concluded that the EMSCAN Lab Express planar near field method overestimates the up-link performance of mobile phones, thus, introducing an error. The up-link performance of mobile phones estimated by the Telia scattered field measurement method agrees with the reference method, but suffers from problems such as extensive measurement time and poor repeatability. The Bluetest reverberation chamber method estimates the uplink performance of mobile phones well. However, the computed Rician K factor from the ML estimator is found to be greater than zero, indicating an inadequacy in the propagation environment inside the reverberation chamber. 

  • 46.
    Homayoun, Saeid
    Luleå Tekniska Universitet.
    The extent and determinates of internet corporate reporting by Malaysian listed companies2011Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In response to the wave of well-publicized corporate scandals, firms in the US, New Zealand, Singapore and other countries have enhanced its transparency via adoption of Internet technology that provides a new way for firm to make continuous disclosure of corporate information. This is an important and emerging financial reporting issue worldwide as more public listed firms now executive their transaction and events online and prepared online and real-time financial reports. The thesis use online research and content analysis of Internet Corporate Reporting (ICR) for a sample of 100 large public listed firms in Malaysia. Results suggest that the slight majority (59 percent) of these firms have developed and implemented a high-quality ICR whereas highest disclosures and scores for ICR are achieved for accounting and financial attributes and lowest for technology related attributes. The increasing use of ICR creates new challenges to management, regulators, and investors as there is no evidence guidance on thissubject. The finding may also propose that new regulatory guidance in corporate governance lead to improved disclosure via ICR. The thesis also find that no firms use the eXtensible Business Reporting Language (XBRL) platform, thus Malaysian public listed firms should start using the XBRL for their counterparts in the United States will be required to adopt for their financial reporting by 2014. This thesis includes the five papers. In the first paper, agency and signaling theories were used to generate hypotheses regarding the determinants of Internet corporate reporting (ICR). The results of univariate analysis and multiple regressions indicated that among firm characteristics variables only profitability (proxy by return of equity), and among corporate governance mechanisms variables only board size (proxy by number of directors) are significantly associated with the extent of Internet corporate reporting. In the second paper, the result indicates that more than 59 percent of Malaysian public listed firms published reasonably well-developed Internet-based reporting and achieved a quality score for ICR. On average, the frequency of the identified items disclosed by the firms for the content of the Web site was higher than for the presentation of information. In the third paper, examine the level of corporate governance disclosure using the internet as a communication tool in improving Corporate Governance. The results show that the maximum raw score for corporate governance obtained by the firms amounted to 17 (71 percent) of the total possible 24 points. The minimum raw score obtained by the firms is 10 (42 percent). The mean score for the 24 items representing corporate governance disclosure is 13.68 (58 percent). The results indicate that most Malaysian firms recognise the importance of practicing good corporate governance and they fully support the initiatives taken by the regulators to promote good corporate governance in Malaysia. In the fourth paper, examine the level of Corporate Social Responsibility disclosure. The maximum raw score for corporate social responsibility obtained by the firms was 7 (or 88% of the total possible 8 points). The minimum score was 0. The average, corporate social responsibility raw score was 4.79 (or 63%). The finding may also propose that new regulatory guidance in Corporate Social Responsibility lead to improved disclosure via Internet Corporate Reporting. In the fifth paper, the study seeks to determine the important factors that drive Malaysian public listed firms to adopt XBRL by conducting open-ended interviews. The result of this study indicates that the most influential factor is the peer adoption of XBRL imposed by the government and its regulators. At the same time, trading partners too pose as an important factor in the adoption of the XBRL reporting format. This study therefore has implications on the policy-makers, regulators, audit firms, and investors encouraging the adoption of XBRL in Malaysian public listed firms.

  • 47.
    Ferrer Coll, Javier
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för elektronik, matematik och naturvetenskap. Högskolan i Gävle, Radio Center Gävle. KTH, KTH Center för Trådlösa System, Wireless@kth.
    RF Channel Characterization in Industrial, Hospital and Home Environments2012Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The rapid development of electronic components has resulted in the emergence of newmobile applications targeted at industry and hospital sectors. Moreover, a lack of availablewireless frequencies as result of the growth of wireless systems is becoming a problem.In this thesis we characterize industrial and hospital environments in order to provide theknowledge necessary to asses present and future development of critical wireless applications.Furthermore, we investigate the possibility of using TV white space by analysingthe interference from secondary to primary user in home environments.

    Some of the wireless solutions used in industries and hospitals come directly fromsystems designed for home or office, such asWLAN and Bluetooth. These systems are notprepared to handle problems associated with interference of impulsive character found inindustrial processes and electrical systems.

    Typically, industrial environments have been classified as reflective environments dueto the metallic structure present in the buildings. In this thesis, we demonstrate that althoughthis may be generally true, some locations in the industry may have special propertieswith wave propagation characteristics in the opposite direction. Stored materials canabsorb wireless signals, resulting in a coverage problem. From the measurement campaignwe are able to distinguish three main classes of indoor environments (highly reflective,medium reflective and low reflective) with different propagation characteristics.

    Improving spectrum efficiency can be a solution to the growing demand for wirelessservices and can increase a system’s robustness against interference, particularly in criticalapplications in industrial and hospital environments. One improvement in spectrum efficiencycan be for secondary consumers to reuse unassigned portions of the TV spectrum ata specific time and geographical location. This thesis studies the effect of inserting whitespace devices in the TV broadcast spectrum. Note that any new model must state the maximumpower allocated to secondary users to avoid harmful interference with the primarysignal.

    The content of this thesis is divided into three parts. The first part is the most comprehensiveand addresses electromagnetic interference and multipath characterization ofindustrial environments. In this part, we have developed a method for channel characterizationfor complex electromagnetic environments and have produced results from differentindustrial environments. The second part presents a preliminary study that characterizesthe electromagnetic interference in a hospital environment. The third part is a study ofsecondary users reusing the TV white spaces.

  • 48.
    Lundin, Mikael
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för elektronik, matematik och naturvetenskap. Institutionen för vilt, fisk och miljö, Sveriges lantbruksuniversitet.
    Size-selection of herring (Clupea harengus membras) in a sustainable fishery2012Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
  • 49.
    Kulander, Maria
    Högskolan i Gävle, Akademin för utbildning och ekonomi, Avdelningen för ekonomi. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Fastigheter och byggande, Bygg- och fastighetsekonomi.
    Do the elderly move at the right time?2013Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [sv]

    Sverige har under många år haft en policy att hjälpa de äldre att kunna bo kvar i sitt nuvarande boende så länge som möjligt. Är detta en bra policy för de äldre och är detta en bra policy ur ett välfärdsperspektiv? Denna studie fokuserar på två aspekter vad gäller de äldres flyttmönster. Stannar de äldre i sitt nuvarande boende för att det är optimalt för hushållet eller beror det på någon form av transaktionskostnader? Är det optimala boendet även optimalt ur ett välfärdsperspektiv vad gäller flyttkedjor för alla ålderskategorier?

    Studien genomfördes i Gävle, en medelstor stad med ca 70 000 invånare ca 100 km norr om Stockholm. Bostadsmarknaden är generellt i jämvikt och priserna är ungefär genomsnittliga för den svenska bostadsmarknaden vilket gör att Gävle är ett bra exempel. Gävle har också en tradition av forskare som är aktiva inom fastighetssektorn. Som inledning till den huvudsakliga enkäten utfördes en pilotstudie under 2011 som fokuserade på avdelningschefer och boende på äldreboenden i Gävle. Frågorna fokuserade på transaktions-kostnader som kan uppkomma när man flyttar och är äldre. Fem avdelningschefer och 18 boende på olika äldreboenden intervjuades. Alternativet till att flytta till äldreboende är att ha hemtjänst. Detta betyder att det är viktigt att särskilja frågan

    "flyttar de äldre till ett mindre boende (downsizing) vid rätt tidpunkt?" och frågan "flyttar de äldre till ett äldreboende vid rätt tidpunkt?". Eftersom pilotstudien visade att beslutet att flytta till ett äldreboende till stor del styrs av de sociala myndigheterna flyttades fokus istället på de som funderar på att flytta till mindre boende. Totalt skickades 1000 enkäter ut till hushåll I åldersgruppen 65-85 år, boende inom den ordinarie bostadssektorn, varav 660 svarade.

    Studien täckte bara till en mindre del informationsaspekten, men om en person är nöjd med sin situation, vilket de allra flesta var, är det snarare brist på initiativ än brist på information som förhindrar flytt, förutom vad gäller de äldre ålderskategorierna. Vad gäller skattesystemet så kunde inga indikationer på att detta förhindrar äldres flyttmönster ses, men slutsatsen kan bero på prisnivån vilket gör att det inte går att generalisera. Även om skattesystemet inte är ett problem så oroar sig många över sina månatliga kostnader. De månatliga kostnaderna kan öka när man flyttar till ett mindre boende eftersom ett nyare boende kan innebära högre månadskostnader. Eftersom det sociala nätverket avtar med åldern och hälsan kan försämras är det möjligt att påverka speciellt en-persons-hushåll över 80 år, boende i 3-5-rumslägenheter. Här kan riktade åtgärder för att underlätta flytt till ett mindre boende eller hjälp att hitta bättre alternativ likt den hjälp som introducerats i Storbritannien ge effekter.

  • 50.
    Halling, Bengt
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad. Högskolan i Gävle, Akademin för hälsa och arbetsliv, Avdelningen för arbets- och folkhälsovetenskap. Högskolan i Gävle, Centrum för belastningsskadeforskning. Högskolan i Gävle, Centrum för logistik och innovativ produktion.
    Lean Implementation: the significance of people and dualism2013Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Lean, with its origins at the Toyota Motor Company, is a concept that is known to increase effectiveness in manufacturing. The Lean concept is now argued to be relevant not only in manufacturing but in service and health-care delivery as well. The reported results of Lean implementation efforts are divided. There are reports that most of the Lean implementation efforts are not reaching the goal; on the other hand, there are reports of promising results. The divided results from Lean implementation efforts show how important it is to research and identify factors that are barriers to successful implementation of Lean. This thesis aims to contribute knowledge about barriers to Lean implementation by collecting empirical findings from manufacturing and health care and structuring the perceived barriers and difficulties to Lean implementation. My first study aimed to compare similarities and divergences in barriers to Lean described by key informants in manufacturing and health care. The data was collected via semi-structured interviews. Findings showed that the perceived difficulties and barriers are much the same in manufacturing and health care. The second study was a case study at a manufacturing firm, researching how the views on Lean of the managers implementing Lean influence its implementation. Data was collected via semi-structured interviews with 20 individuals and covered all hierarchical management levels in the company. Findings showed that managers' views on Lean influence the implementation but also that learning during the implementation process can alter managers' views of Lean. The third study aimed to research how management of Lean is described in the literature. This was done through a literature review. The findings showed that Lean management is a matter of dualism, consisting of two complementary systems of action, management and leadership, which are related to the two basic principles of Lean, continuous improvement and respect for the people.

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