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  • 151.
    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. 

  • 152.
    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

  • 153.
    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.

  • 154.
    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.

  • 155.
    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.

  • 156.
    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.

  • 157.
    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.

  • 158.
    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.

  • 159.
    Alizadeh, Mahmoud
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. Department of Signal Processing, ACCESS Linnaeus Center, The Royal Institute of Technology (KTH), Stockholm, Sweden.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    A two-tone test for characterizing nonlinear dynamic effects of radio frequency amplifiers in different amplitude regions2016In: Measurement, ISSN 0263-2241, E-ISSN 1873-412X, Vol. 89, p. 273-279Article in journal (Refereed)
    Abstract [en]

    A new two-tone test method for radio frequency power amplifiers is presented. The test signal is a two-tone probing-signal superimposed on large-signals of different amplitude. The amplifier is, thus, excited in different amplitude regions. The amplitude and phase of the 3rd order intermodulation (IM) products are measured vs. frequency spacing and probing-signal amplitude in each region. The IM magnitude is a measure of the nonlinearity, while the frequency dependence and asymmetry are measures of the memory effects in the different regions. A Doherty and a class-AB amplifier were tested. For both amplifiers the IM magnitude increased by ∼15 dB from the lowest to the highest amplitude region. For the Doherty amplifier the behavior of the IM products vs. frequency spacing was similar in all regions, indicating similar memory effects. For the class-AB amplifier the IM vs. frequency spacing was significantly different in the different regions, which indicates different memory effects.

  • 160.
    Alizadeh, Mahmoud
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Händel, Peter
    Department of information science and engineering Royal Institute of Technology (KTH), Stockholm, Sweden.
    Characterization of Volterra Kernels for RF Power Amplifiers Using a Two-Tone Signal and a Large-Signal2018In: 2018 International Conference on Communications, COMM 2018 - Proceedings, Institute of Electrical and Electronics Engineers (IEEE), 2018, Vol. 1, p. 351-356Conference paper (Refereed)
    Abstract [en]

    The 3rd-order Volterra kernels of a radio frequency (RF) power amplifier (PA) are characterized using a large-signal and a two-tone probing-signal. In this technique, the magnitude and phase asymmetries of the kernels of the PA excited by the probing-signal are analyzed in different amplitude regions of the large-signal. The device under test is a class-AB PA operating at 2.14 GHz. The maximum sweeping frequency space of the probing-signal is 20 MHz. The results indicate that the Volterra kernels of the PA show different behaviors (frequency dependency and asymmetry) in different regions.

  • 161.
    Alizadeh, Mahmoud
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. KTH.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Händel, Peter
    KTH.
    Isaksson, Magnus
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    A new Block-Structure Modeling Technique for RF Power Amplifiers in a 2x2 MIMO System2017In: 13th International Conference on Advanced Technologies, Systems and Services in Telecommunications (TELSIKS) / [ed] Milovanovic, B. D.; Doncov, N. S.; Stankovic, Z. Z.; Dimitrijevic, T. Z., IEEE , 2017, p. 224-227Conference paper (Refereed)
    Abstract [en]

    A new block-structure behavioral model is proposed for radio frequency power amplifiers in a 2x2 multiple-input multiple-output system including input cross-talk. The proposed model forms kernels of blocks of different nonlinear order that correspond to the significant frequency response of measured frequency domain Volterra kernels. The model can therefore well describe the input-output relationships of the nonlinear dynamic behavior of PAs. The proposed model outperforms conventional models in terms of model errors.

  • 162. Al-Khamisi, Rami
    et al.
    Sjöberg, Stefan
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Social work.
    Social mobilisering och nya sociala rörelser2018In: Samhällsarbete: aktörer, arenor och perspektiv / [ed] Sjöberg, S. & Turunen, P., Lund: Studentlitteratur AB, 2018, 1, p. 277-295Chapter in book (Refereed)
    Abstract [sv]

    Författarna diskuterar nya sociala förortsrörelser som försöker motverka den sociala exkludering och gentrifiering som blir allt mer synlig. Dessa rörelser kräver social upprustning av miljonprogrammen och inkludering i demokratiska beslutsprocesser. De har vuxit fram genom organisering underifrån av människor som bor och vuxit upp i området. I detta kapitel ligger fokus på den förortsbaserade organisationen Megafonen som arbetar med social mobilisering av medborgarna på Järvafältet i Stockholm, för att bidra till framväxandet av en social rörelse mot social exkludering och för ökat medborgarinflytande, social upprustning och social rättvisa. Som framtida utmaningar för mobiliserande samhällsarbete lyfter författarna den s.k. rörelsejuridiken.  Författarna förespråkar ett samhällsarbete som bygger påmedvetandegörande , skapande av kollektiv identitet och samhörighet, stödjande av aktivering och deltagande, samt mobilisering av de utsatta grupperna själva för social förändring.

  • 163.
    Allaire, G.
    et al.
    Ecole Polytechnique, Palaiseau Cedex, France.
    Pankratova, Iryna
    Narvik University College, Narvik, Norway.
    Piatnitski, A.
    Lebedev Physical Institute RAS, Moscow, Russia.
    Homogenization and concentration for a diffusion equation with large convection in a bounded domain2012In: Journal of Functional Analysis, ISSN 0022-1236, E-ISSN 1096-0783, Vol. 262, no 1, p. 300-330Article in journal (Refereed)
    Abstract [en]

    We consider the homogenization of a non-stationary convection–diffusion equation posed in a bounded domain with periodically oscillating coefficients and homogeneous Dirichlet boundary conditions. Assuming that the convection term is large, we give the asymptotic profile of the solution and determine its rate of decay. In particular, it allows us to characterize the “hot spot”, i.e., the precise asymptotic location of the solution maximum which lies close to the domain boundary and is also the point of concentration. Due to the competition between convection and diffusion, the position of the “hot spot” is not always intuitive as exemplified in some numerical tests.

  • 164.
    Allaire, G.
    et al.
    Ecole Polytechnique, Palaiseau Cedex, France.
    Pankratova, Iryna
    Narvik University College, Narvik, Norway; Ecole Polytechnique, Palaiseau Cedex, France.
    Piatnitski, A.
    Narvik University College, Narvik, Norway; Lebedev Physical Institute RAS, Moscow, Russia.
    Homogenization of a nonstationary convection-diffusion equation in a thin rod and in a layer2012In: SeMA Journal, ISSN 1575-9822, Vol. 58, no 1, p. 53-95Article in journal (Refereed)
    Abstract [en]

    The paper deals with the homogenization of a non-stationary convection-diffusion equation defined in a thin rod or in a layer with Dirichlet boundary condition. Under the assumption that the convection term is large, we describe the evolution of the solution’s profile and determine the rate of its decay. The main feature of our analysis is that we make no assumption on the support of the initial data which may touch the domain’s boundary. This requires the construction of boundary layer correctors in the homogenization process which, surprisingly, play a crucial role in the definition of the leading order term at the limit. Therefore we have to restrict our attention to simple geometries like a rod or a layer for which the definition of boundary layers is easy and explicit.

  • 165.
    Allelin, Majsa
    et al.
    Göteborgs universitet.
    Kallifatides, Markus
    Handelshögskolan i Stockholm.
    Sjöberg, Stefan
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Social work.
    Skyrman, Viktor
    Handelshögskolan i Stockholm.
    Välfärdsmodellens omvandling: det privata kapitalets utvidgning i den offentliga sektorn2018Report (Other academic)
    Abstract [sv]

    Den universella välfärdsmodell, som tillämpats i Sverige sedan andra världskriget, vägleddes av ambitionen att hålla marknadsintressen utanför välfärden för att undvika ojämlik tillgång och kvalitet samt för att stärka den demokratiska styrningen av välfärdssektorn. Sverige präglades därmed av en välutvecklad offentlig sektor med god tillgång till offentlig service.Den här rapporten kan dock genom omfattande statistiska studier visa hur den svenska välfärdsmodellen sedan 80-talet och framåt har genomgått genomgripande förändringar. Resultaten är bland annat:

    • Antalet privata aktörer i välfärdssektorn ökar som en följd av politiskt skapade välfärdsmarknader.

    • Gemensamma skattemedlen finansierar i högre grad privata välfärdstjänster, som i allt större utsträckning utförs av stora koncernägda aktiebolag, liksom dessa företags vinster.

    • Omfattande privatiseringar av gemensamt ägande har genomförts.

    • Andelen offentligt anställda har minskat med 10 procentenheter och antalet statsanställda har halverats, medan antalet sysselsatta i privat välfärdsverksamhet fyrdubblats.

    • En högre andel skatter går i allt större utsträckning till att finansiera välfärdsverksamhet som bedrivs av det privata näringslivet.

    • Offentlig sektors totala andel av samhällsekonomin har minskat från 60 procent till 50 procent av BNP.

    Dessa resultat tyder sammanfattningsvis på att den svenska välfärdsmodellen har genomgått kritiska förändringar vars följder inneburit att en omfattande omfördelning av makt, resurser och inflytande har skett från den demokratiskt styrda gemensamma sektorn – till den marknadsstyrda privata sektorn. Den svenska universella välfärdsmodellen som en gång hyllades har ersatts av en allt mer marknadsliberal modell. Bland konsekvenserna finns försämrad jämlikhet i tillgången till exempelvis skola, vård och omsorg, mindre ekonomisk omfördelningspolitik och mindre demokratisk styrning. Samtidigt går en allt växande andel av medborgarnas skattepengar till de privata välfärdsföretagens vinster.

  • 166.
    Allelin, Majsa
    et al.
    Göteborgs universitet.
    Kallifatides, Markus
    Handelshögskolan i Stockholm.
    Sjöberg, Stefan
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Social work.
    Skyrman, Viktor
    Handelshögskolan i Stockholm.
    Ägande- och förmögenhetsstrukturen och dess förändring sedan 19802018Report (Other academic)
    Abstract [sv]

    Den här rapporten visar, genom omfattande studier av en mängd tidigare genomförda undersökningar om ägande och förmögenhetsförhållanden i Sverige, att koncentrationen av makt och ägande har blivit allt mer ojämlik. Resultaten är bland annat att:

    • Ungefär hälften av den samlade svenska ekonomin ägsnumera från utlandet.

    • Det utländska ägandet på Stockholmsbörsen har ökat från 4 procent år 1979 till 39,4 procent 2016.

    • Det offentliga bolagsägandet har minskat och antalet anställda i statliga företag har halverats från 310 000 år 1980 till 158 000 år 2015.

    • Det institutionella ägandet har ökat och utgör cirka 20 procent av ägandet i de börsnoterade bolagen.

    • Det så kallade riskkapitalet har vuxit kraftfullt i omfattning och störst i sektorn är Wallenbergkontrollerade EQT.

    • I de stora börsnoterade bolagen på Stockholmsbörsen har den största ägarens andel av röstetalet ökat från i genomsnitt 26,8 procent till 31,2 procent av bolagsstämmans röster.

    • De 15 största finansfamiljerna styrde år 2017 bolag värda 4 935 miljarder kronor. Som jämförelse var Sveriges totala BNP samma år 4 604 miljarder kronor.

    • Familjen Wallenberg kontrollerade företag värderade till närmare 2 000 miljarder kronor.

    • Vad gäller de samlade förmögenheterna så har den allra rikaste procentens andel av de samlade förmögenheterna fördubblats från 20,5 procent 1978 till 39,6 procent 2006 och har fortsatt öka sedan dess.

    • Antalet svenska miljardärer har ökat från 83 personer 2001 till 178 år 2016.

    För att samhällsutvecklingen ska kunna vändas i riktning mot ökad jämlikhet krävs det att den breda vänstern tar kampen för att återskapa former för reglering och begränsningar av kapitalets makt både i Sverige men också internationellt i en allt mer globaliserad värld. Utvecklandet av ett nytt gemensamt projekt, som utgör ett verkligt alternativ till den ojämlikhetsskapande marknadsliberalismen, är av avgörande betydelse för socialdemokratins framtid.

  • 167.
    Allelin, Majsa
    et al.
    Göteborgs universitet.
    Kallifatides, Markus
    Handelshögskolan i Stockholm.
    Sjöberg, Stefan
    University of Gävle, Faculty of Health and Occupational Studies, Department of Social Work and Psychology, Social work.
    Skyrman, Viktor
    Handelshögskolan, Stockholm.
    Suhonen, Daniel
    Katalys - Institut för facklig idéutveckling.
    Femton familjer kontrollerar sjuttio procent av börsvärdet2018In: Dagens nyheter, Vol. 14 aprilArticle in journal (Other (popular science, discussion, etc.))
  • 168.
    Almaz Eriksen, Elisabet
    et al.
    Oslo University College.
    Grannäs, Jan
    University of Gävle, Department of Education and Psychology, Ämnesavdelningen för didaktik.
    Nordqvist, Ingrid
    University of Gävle, Department of Education and Psychology, Ämnesavdelningen för didaktik.
    Björklund, Elisabeth
    University of Gävle, Department of Education and Psychology, Ämnesavdelningen för didaktik.
    The ASSIST course plan2008Report (Other academic)
  • 169. Alrutz, Marie
    et al.
    Berg, Henrik
    Berndtson, Rolf
    Curman, Barbro
    Ekstrand, Lars
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    Eliasson, Maria
    Frenkel, Lillemor
    Frölander, Carin
    Gustavsson, Tomas
    Helgeson, Tore
    Henning Planck, Ebba
    Holgersson, Charlotte
    Iveroth, Einar
    Jansson, Tomas
    Jerbrant, Anna
    Kamél, Elisabeth
    Kihlström, Eva
    Kåresjö, Bo
    Lindgren, Monica
    Ludvig, Lindlöf
    Molinder, Olof
    Oscarson, Kjerstin
    Packendorff, Johann
    Rapp Ricciardi, Max
    Runsten, Philip
    Sjöholm, Håkan
    Sundin, Ola
    Säfström, Carita
    Trossing, Malin
    Wallmon, Monika
    Villför Larsson, Pia
    Wenell, Torbjörn
    Andreas, Werr
    Wikforss, Örjan
    Projektledning2013Book (Other (popular science, discussion, etc.))
    Abstract [sv]

    Projektledning är ett yrke med egen certifiering. Det pågår en spännande utveckling inom området och det blir allt viktigare att hålla sig ajour med utvecklingen.

    Det övergripande målet med den här handboken är att vara en ständigt aktuell heltäckande bok om projektar­bete. Innehållsmässigt täcker den både frågor som har med struktur och styrning att göra och frågor om ledning av människor och mänskliga processer i grupp. Kompetens inom projekt byggs av både kunskap och erfarenhet. Vi följer kontinuerligt aktuell forskning inom dessa områden och bjuder in intressanta forskare att medverka som författare. Vi skildrar verkliga projekt och låter erfarenheterna få plats, både de bästa erfarenheterna och de utmaningar som man tagit sig igenom.

    Handboken är levande och det innebär att artiklar tas bort för att ge plats för nya, i takt med att den uppdateras fortlöpande.

  • 170. Alsaid, Loai Ali
    et al.
    Mutiganda, Jean Claude
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    Political and business leaderships in managing public service organisation2018In: Corporate Ownership & Control, ISSN 1727-9232, E-ISSN 1810-3057, Vol. 15, no 4Article in journal (Refereed)
    Abstract [en]

    This study analyses the relationship between the state’s political ideologies and the implementation of cost management strategies during the re-privatisation of a public sector organisation. Drawing on the Dillard et al.’s (2004) conceptual framework, we conducted a case study in a public sector organisation operating in the electricity market of Egypt. Data was gathered through document analysis, interviews, meetings observations and continuous interactions with key informants from 2013 to 2014. The findings show that the implementation of cost management strategies had a political basis, grounded in the state’s reformative ideologies concerning re-privatisation of the public sector organisation. The re-privatisation failed because the state failed to convince a potential international investor. A theoretical contribution is to show the relevance of cost management strategies when used as a political tool to achieve a business goal, such as improving a public sector organisation’s performance management in a developing country. This is the first empirical case study to analyse management accounting change based on the state’s political ideologies in the Maghreb region of Africa. The key difference between this global trend elsewhere and in the Egyptian State, as in some other Islamic countries, is that Egypt was both nationalistic and militarised.

  • 171.
    Alsins, J.
    et al.
    University of Uppsala, Department of Physical Chemistry, Uppsala, Sweden.
    Björling, Mikael
    Royal Institute of Technology, Physical Chemistry, Stockholm, Sweden.
    Furó, I.
    Royal Institute of Technology, Physical Chemistry, Stockholm, Sweden.
    Egle, V.
    University of Uppsala, Department of Physical Chemistry, Uppsala, Sweden; Latvian State Inst. of Wood Chem., Riga, Latvia.
    Dimer formation of a stilbenesulphonic acid salt in aqueous solution1999In: Journal of Physical Organic Chemistry, ISSN 0894-3230, E-ISSN 1099-1395, Vol. 12, no 3, p. 171-175Article in journal (Refereed)
    Abstract [en]

    The steady-state and time-resolved fluorescence and 1H NMR spectra of a stilbenesulphonic acid salt, commonly used as an optical brightening agent, was studied as a function of concentration in aqueous solution. The aggregates, formed at higher concentrations, were shown to be predominantly dimers with the central stilbene moieties of the molecules stacked plane-parallel. The equilibrium constant for the dimer formation at 25°C was obtained from both NMR and fluorescence measurements.

  • 172.
    Ameen, Arman
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Reducing energy usage in multi-family housing2019In: 2019 9th International Conference on Future Environment and Energy 9–11 January 2019, Osaka, Japan, Institute of Physics Publishing (IOPP), 2019, Vol. 257, article id 012030Conference paper (Refereed)
    Abstract [en]

    The energy usage in residential sector have been around 22% of the total energy use in the world and increasing due to the population growth and higher living standards. The energy sources for this are made up primarily of non-renewable energy resources which generates a large amount of global greenhouse gases. A lot of countries have implemented various regulations and rules to reduce the energy usage in buildings and promoting the use of renewable energy technologies. This paper presents a parametric study of a typical multi-family building in its pre-design stage. The climate location used is Sweden (Gothenburg) and Japan (Osaka). The aim of the study is to compare various configurations and to examine how they affect the energy use. The most interesting configurations are the use of heat pump and solar cells. Other configurations that are examined are infiltration levels, pressure coefficients, wind impact, ventilation with heat recovery, ventilation scheduling, building orientation and finally changing U-values in the building material. Results of this study show that the energy saving, by utilizing a heat pump and solar panels, can reduce the total energy use by 34.9% for Gothenburg and 32% for Osaka. The results also show that the difference in total energy use between the two cities reduce substantially (3% difference) when utilizing a heat pump in combination with solar panels.

  • 173.
    Ameen, Arman
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Larsson, Ulf
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Karimipanah, Taghi
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Experimental Investigation of Ventilation Performance of Different Air Distribution Systems in an Office Environment: Heating Mode2019In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 12, no 10, article id 1835Article in journal (Refereed)
    Abstract [en]

    A vital requirement for all-air ventilation systems are their functionality to operate both in cooling and heating mode. This article experimentally investigates two newly designed air distribution systems, corner impinging jet (CIJV) and hybrid displacement ventilation (HDV) in comparison against a mixing type air distribution system. These three different systems are examined and compared to one another to evaluate their performance based on local thermal comfort and ventilation effectiveness when operating in heating mode. The evaluated test room is an office environment with two workstations. One of the office walls, which has three windows, faces a cold climate chamber. The results show that CIJV and HDV perform similar to a mixing ventilation in terms of ventilation effectiveness close to the workstations. As for local thermal comfort evaluation, the results show a small advantage for CIJV in the occupied zone. Comparing C2-CIJV to C2-CMV the average draught rate (DR) in the occupied zone is 0.3% for C2-CIJV and 5.3% for C2-CMV with the highest difference reaching as high as 10% at the height of 1.7 m. The results indicate that these systems can perform as well as mixing ventilation when used in offices that require moderate heating. The results also show that downdraught from the windows greatly impacts on the overall airflow and temperature pattern in the room.

  • 174.
    Ameen, Arman
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Larsson, Ulf
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Karimipanah, Taghi
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Experimental investigation of ventilation performance of different air distribution systems in an office environment – cooling mode2019In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 12, no 7, article id 1354Article in journal (Refereed)
    Abstract [en]

    The performance of a newly designed corner impinging jet air distribution method with an equilateral triangle cross section was evaluated experimentally and compared to that of two more traditional methods (mixing and displacement ventilation). At nine evenly chosen positions with four standard vertical points, air velocity, turbulence intensity, temperature, and tracer gas decay measurements were conducted for all systems. The results show that the new method behaves as a displacement ventilation system, with high air change effectiveness and stratified flow pattern and temperature field. Both local air change effectiveness and air exchange effectiveness of the corner impinging jet showed high quality and promising results, which is a good indicator of ventilation effectiveness. The results also indicate that there is a possibility to slightly lower the airflow rates for the new air distribution system, while still meeting the requirements for thermal comfort and indoor air quality, thereby reducing fan energy usage. The draught rate was also lower for corner impinging jet compared to the other tested air distribution methods. The findings of this research show that the corner impinging jet method can be used for office ventilation.

  • 175.
    Ameen, Arman
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Choonya, Gasper
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Experimental Evaluation of the Ventilation Effectiveness of Corner Stratum Ventilation in an Office Environment2019In: Buildings, ISSN 2075-5309, E-ISSN 2075-5309, Vol. 9, no 7, article id 169Article in journal (Refereed)
    Abstract [en]

    An experimental study was conducted in a room resembling an office in a laboratory environment. The study involved investigating the ability of corner-placed stratum ventilation in order to evaluate the ventilation’s effectiveness and local thermal comfort. At fixed positions, the air temperature, air velocity, turbulence intensity, and tracer gas decay measurements were carried out. The results show that corner-placed stratum ventilation behaves very similar to a mixing ventilation system when considering air change effectiveness. The performance of the system was better at lower supply air flow rates for heat removal effectiveness. For the heating cases, the draught rates were all very low, with the maximum measured value of 12%. However, for the cooling cases, the maximum draught rate was 20% and occurred at ankle level in the middle of the room.

  • 176.
    Amein, T
    et al.
    Department of Cell and Molecular Biology, Göteborg University.
    Olsson, C H B
    Department of Cell and Molecular Biology, Göteborg University.
    Wikstrom, M
    Findus R & D AB, Bjuv, Sweden.
    Wright, Sandra A. I.
    Department of Cell and Molecular Biology, Göteborg University.
    First report in Sweden of downy mildew on parsley caused by Plasmopara petroselini2006In: Plant Disease, ISSN 0191-2917, E-ISSN 1943-7692, Vol. 90, no 1, p. 111-111Article in journal (Refereed)
  • 177.
    Amein, Tahsein
    et al.
    Dept Cell & Mol Biol, Gothenburg, Sweden .
    Wright, Sandra A. I.
    Univ Studi Molise, Dipartimento Sci Anim Vegetali & Ambiente, Italy .
    Wikstroem, Mariann
    Jordbruksverket Växtskyddscentralen Alnarp, Sweden .
    Koch, Eckhard
    JKI, Inst Biol Control, Darmstadt, Germany .
    Schmitt, Annegret
    JKI, Inst Biol Control, Darmstadt, Germany .
    Stephan, Dietrich
    JKI, Inst Biol Control, Darmstadt, Germany .
    Jahn, Marga
    JKI, Inst Strategies & Technol Assessment Plant Protec, Kleinmachnow, Germany .
    Tinivella, Federico
    Univ Turin, Italy .
    Gullino, M. Lodovica
    Univ Turin, Italy .
    Forsberg, Gustaf
    Seedgard AB, Uppsala, Sweden .
    Werner, Sigrid
    Hild Samen GmbH, Marbach Am Neckar, Germany.
    van der Wolf, Jan
    Plant Res Int, Netherlands.
    Groot, Steven Pc
    Plant Res Int, Netherlands.
    Evaluation of non-chemical seed treatment methods for control of Alternaria brassicicola on cabbage seeds2011In: Journal of Plant Diseases and Protection, ISSN 1861-3829, E-ISSN 1861-3837, Vol. 118, no 6, p. 214-221Article in journal (Refereed)
    Abstract [en]

    Due to the lack of foliar fungicide use, the organic production of Brassica seeds free of Alternaria spp. is difficult. Therefore, effective seed treatments certified for use in organic farming are needed to eradicate or at least effectively reduce the seed-borne inoculum. We here report results of greenhouse and field experiments in which non-chemical seed treatments were tested for control of A. brassicicola on cabbage seeds naturally infested with the pathogen. In greenhouse experiments, significant improvements were obtained by seed treatment with some commercialised and experimental microbial biocontrol agents, an emulsion of thyme oil in water (0.1%) and by the tested physical seed treatments methods (i.e. hot water, aerated steam and electron seed treatment). Resistance inducers tended to increase the percentage of healthy plants, but the effects were statistically not significant. Generally the combination of physical treatments with the effective agents did not result in improved performance. Positive effects on crop establishment and yield by the same treatments were also observed in field tests. Overall the results indicate that several options for non-chemical control of A. brassicicola on Brassica seeds exist that are comparable in efficacy to the chemical standard Aatiram (active ingredient thiram) used in this study.

  • 178.
    Amin, A.
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences. Teleconnect GmbH, Dresden, Germany; University of Applied Sciences Dresden, Dresden, Germany.
    Bluschke, A.
    Teleconnect GmbH, Dresden, Germany.
    Emery, S.
    Innodul AG, Zürich, Switzerland.
    Krüger, F.
    Teleconnect GmbH, Dresden, Germany; University of Applied Sciences Dresden, Dresden, Germany.
    Matthews, M.
    Teleconnect GmbH, Dresden, Germany.
    Rietzsch, P.
    Teleconnect GmbH, Dresden, Germany.
    Steglich, R.
    Contec Steuerungstechnik and Automation GmbH, Ebbs, Austria.
    Multi-carrier transmission over si-pof2011In: POF 2011: 20th International Conference on Plastic Optical Fibers - Conference Proceeding, 2011, p. 81-86Conference paper (Refereed)
    Abstract [en]

    Multi-carrier modulation (MCM) is today’s method of choice for communication systems. This is also true for SI-POF. The basics of MCM and special characteristics for the optical transmission using SI-POF are explained within this paper. Current approaches for MCM over SI-POF are described: Teleconnect’s G.hn based solution for home networking and Innodul’s DMT-based Gigabit solution.

  • 179.
    Amin, Hadi
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Sjöberg, Lars
    Division of Geodesy and satellite positioning, KTH.
    Bagherbandi, Mohammad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    A global vertical datum defined by the conventional geoid potential and the Earth ellipsoid parameters2019In: Journal of Geodesy, ISSN 0949-7714, E-ISSN 1432-1394Article in journal (Refereed)
    Abstract [en]

    The geoid, according to the classical Gauss–Listing definition, is, among infinite equipotential surfaces of the Earth’s gravity field, the equipotential surface that in a least squares sense best fits the undisturbed mean sea level. This equipotential surface, except for its zero-degree harmonic, can be characterized using the Earth’s global gravity models (GGM). Although, nowadays, satellite altimetry technique provides the absolute geoid height over oceans that can be used to calibrate the unknown zero-degree harmonic of the gravimetric geoid models, this technique cannot be utilized to estimate the geometric parameters of the mean Earth ellipsoid (MEE). The main objective of this study is to perform a joint estimation of W0, which defines the zero datum of vertical coordinates, and the MEE parameters relying on a new approach and on the newest gravity field, mean sea surface and mean dynamic topography models. As our approach utilizes both satellite altimetry observations and a GGM model, we consider different aspects of the input data to evaluate the sensitivity of our estimations to the input data. Unlike previous studies, our results show that it is not sufficient to use only the satellite-component of a quasi-stationary GGM to estimate W0. In addition, our results confirm a high sensitivity of the applied approach to the altimetry-based geoid heights, i.e., mean sea surface and mean dynamic topography models. Moreover, as W0 should be considered a quasi-stationary parameter, we quantify the effect of time-dependent Earth’s gravity field changes as well as the time-dependent sea level changes on the estimation of W0. Our computations resulted in the geoid potential W0 = 62636848.102 ± 0.004 m2 s−2 and the semi-major and minor axes of the MEE, a = 6378137.678 ± 0.0003 m and b = 6356752.964 ± 0.0005 m, which are 0.678 and 0.650 m larger than those axes of GRS80 reference ellipsoid, respectively. Moreover, a new estimation for the geocentric gravitational constant was obtained as GM = (398600460.55 ± 0.03) × 106 m3 s−2.

  • 180.
    Amin, Md. Khaled
    et al.
    American International University-Bangladesh, Dhaka, Bangladesh.
    Chowdhury, Ehsanul
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    Zaman, Mahmud Habib
    North South University, Dhaka, Bangladesh.
    Understanding the Determinants of Technology Driven Services Adoption by the Rural Consumers in Bangladesh2018In: Journal of Business Administration, ISSN 1680-9823, Vol. 38, no 1 & 2, p. 103-115Article in journal (Refereed)
    Abstract [en]

    This study sought to ascertain the possible determinants that sway rural consumers’ behavioral intention to use technology driven services in Bangladesh. Using the self-administrated questionnaire followed by several in-depth interviews and focus group discussions (FGDs) as supporting instruments, this study analyzed information gathered from one hundred and three respondents, drawn purposively from a village locally known as Dollar Bazar, situated in Manikganj district of Bangladesh.  All respondents were provided with the structured and self-administrated questionnaires and advised to quantify their responses in a 7-point Likert scale ranging from Strongly Disagree (SD) to Strongly Agree (SA). Questionnaire items were primarily adopted from prior studies, pertinent to Information Communication Technologies (ICTs) diffusion, adoption, and acceptance. Results of the study reveal that the three retained observed variables; Service Perception (SP), Perceived Interaction (PI), Intention to Use (ITU) have good degree of internal consistency. Moreover, confirmatory factor analysis (CFA) results brought out the facts that the variable, namely Perceived Interaction (PI) is significantly affecting the dependent variable while Service Perception (SP) has no significant effect on the intention to use which are quite consistent with the earlier estimates in this field. Findings of this study have theoretical contributions as it directly contributes by enhancing the outlook of the literature of technology adoption, and provide managerial implications for ICT driven organizations (i.e. Telecom companies, Value Added service [VAS] providers, Financial Institutions) by enhancing knowledge regarding the rural consumers of Bangladesh and their behavior. 

  • 181.
    Amin, Shoaib
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. KTH Royal Institute of Technology, Stockholm, Sweden.
    Characterization and Linearization of Multi-band Multi-channel RF Power Amplifiers2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The World today is deeply transformed by the advancement in wireless technology. The envision of a smart society where interactions between physical and virtual dimensions of life are intertwined and where human interaction is mediated by machines, e.g., smart phones, demands increasingly more data traffic. This continual increase in data traffic requires re-designing of the wireless technologies for increased system capacity and flexibility. In this thesis, aspects related to behavioral modeling, characterization, and linearization of multi-channel/band power amplifiers (PAs) are discussed.

    When building a model of any system, it is advantageous to take into account the knowledge of the physics of the system and include into the model. This approach could help to improve the model performance. In this context, three novel behavioral models and DPD schemes for nonlinear MIMO transmitters are proposed.

    To model and compensate distortions in GaN based RF PAs in presence of long-term memory effects, novel models for SISO and concurrent dual-band PAs are proposed. These models are based on a fixed pole expansion technique and have infinite impulse response. They show substantial performance improvement. A behavioral model based on the physical knowledge of the concurrent dual-band PA is derived, and its performance is investigated both for behavioral modeling and compensation of nonlinear distortions.

    Two-tone characterization is a fingerprint method for the characterization of memory effects in dynamic nonlinear systems. In this context, two novel techniques are proposed. The first technique is a dual two-tone characterization technique to characterize the memory effects of self- and cross-modulation products in concurrent dual-band transmitter. The second technique is for the characterization and analysis of self- and cross-Volterra kernels of nonlinear 3x3 MIMO systems using three-tone signals.

  • 182.
    Amin, Shoaib
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Characterization and Linearization of Multi-channel RF Power Amplifiers2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The demands for high data rates and broadband wireless access requirethe development of wireless systems that can support wide and multi-bandsignals. To deploy these signals, new radio frequency (RF) front-ends are requiredwhich impose new challenges in terms of power consumption efficiencyand sources of distortion e.g., nonlinearity. These challenges are more pronouncedin power amplifiers (PAs) that degrade the overall performance ofthe RF transmitter.Since it is difficult to optimize the linearity and efficiency characteristicsof a PA simultaneously, a trade-off is needed. At high input power, a PAexhibits high efficiency at the expense of linearity. On the other hand, atlow input power, a PA is linear at the expense of the efficiency. To achievelinearity and efficiency at the same time, digital pre-distortion (DPD) is oftenused to compensate for the PA nonlinearity at high input power. In case ofmulti-channel PAs, input and output signals of different channels interactwith each other due to cross-talk. Therefore, these PAs exhibit differentnonlinear behavior than the single-input single-output (SISO) PAs. The DPDtechniques developed for SISO PAs do not result in adequate performancewhen used for multi-channel PAs. Hence, an accurate behavioral modeling isessential for the development of DPD for multi-channel RF PAs.In this thesis, we propose three novel behavioral models and DPD schemesfor nonlinear multiple-input multiple-output (MIMO) transmitters in presenceof cross-talk. A study of the source of cross-talk in MIMO transmittershave been investigated to derive simple and powerful modeling schemes.These models are extensions of a SISO generalized memory polynomial model.A comparative study with a previously published MIMO model is also presented.The effect of coherent and partially non-coherent signal generationon DPD performance is also highlighted. It is shown experimentally thatwith partially non-coherent signal generation, the performance of the DPDdegrades compared to coherent signal generation.In context of multi-channel RF transmitters, PA behavioral models andDPD schemes suffer from a large number of model parameters with the increasein nonlinear order and memory depth. This growth leads to highcomplexity model identification and implementation. We have designed aDPD scheme for MIMO PAs using a sparse estimation technique for reducingmodel complexity. This technique also increases the numerical stability whenlinear least square estimation model identification is used.A method to characterize the memory effects in a nonlinear concurrentdual-band PAs is also presented. Compared to the SISO PAs, concurrentdual-band PAs are not only affected by intermodulation distortions but alsoby cross-modulation distortions. The characterization of memory effects inconcurrent dual-band transmitter is performed by injecting a two-tone testsignal in each input channel of the transmitter. Asymmetric energy surfacesare introduced for the intermodulation and cross-modulation products, whichcan be used to identify the power and frequency regions where the memory effects are dominant.

  • 183.
    Amin, Shoaib
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. Dept of Signal Processing, KTH Royal Institute of Technology, Stockholm, Sweden.
    Händel, Peter
    Dept of Signal Processing, KTH 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.
    Characterization and modeling of RF amplifiers with multiple input signals2016Conference paper (Refereed)
    Abstract [en]

    A characterization technique for RF PAs excited with multiple signals is presented. The technique can be used for characterization of memory effects in IM/CM products. The extracted information can in return be of use for modifying behavioral models to better capture memory in IM/CM products.

  • 184.
    Amin, Shoaib
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. Department of Signal Processing, School of Electrical Engineering, KTH.
    Händel, Peter
    Department of Signal Processing, School of Electrical Engineering, KTH.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Digital Predistortion of Single and Concurrent Dual Band Radio Frequency GaN Amplifiers with Strong Nonlinear Memory Effects2017In: IEEE transactions on microwave theory and techniques, ISSN 0018-9480, E-ISSN 1557-9670, Vol. 65, no 7, p. 2453-2464, article id 7855827Article in journal (Refereed)
    Abstract [en]

    Electrical anomalies due to trapping effects in Gallium Nitride (GaN) power amplifiers (PAs)give rise to long-term or strong memory effects. We propose novel models based on infinite impulse response (IIR) fixed pole expansion techniques for the behavioural modeling and digital pre-distortion of single-input-single-output (SISO) and concurrent dual-bandGaN PAs. Experimental results show that the proposed models outperform the corresponding finite impulse response (FIR) models by up to 17 dB for the same number of model parameters. For the linearization of a SISO GaN PA the proposed models give adjacent channel power ratios (ACPRs) that are 7 to 17 dBlower than the FIR models. For the concurrent dual-band case, the proposed models give ACPRs that are 9to 14 dB lower than the FIR models.

  • 185.
    Amin, Shoaib
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. ACCESS Linnaeus Centre, Department of Signal Processing, KTH Royal Institute of Technology, Stockholm.
    Khan, Zain Ahmed
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. ACCESS Linnaeus Centre, Department of Signal Processing, KTH Royal Institute of Technology, Stockholm.
    Isaksson, Magnus
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Händel, Peter
    ACCESS Linnaeus Centre, Department of Signal Processing, KTH Royal Institute of Technology, Stockholm.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Concurrent dual-band power amplifier model modification using dual two-tone test2016In: 46th Europena Microwave Conference (EUMC) 2016, 2016, p. 186-189Conference paper (Refereed)
    Abstract [en]

    A dual two-tone technique for the characterization of memory effects in concurrent dual-band transmitters is revisited to modify a 2D-DPD model for the linearization of concurrent dual-band transmitters. By taking into account the individual nonlinear memory effects of the self- and cross-kernels, a new2D modified digital pre-distortion (2D-MDPD) model is proposed,which not only supersedes the linearization performance but also reduces the computational complexity compared to the 2DDPDmodel in terms of a number of floating point operations(FLOPs). Experimental results show an improvement of 1.7 dBin normalized mean square error (NMSE) and a 58% reduction in the number of FLOPs.

  • 186.
    Amin, Shoaib
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. KTH.
    Landin, Per
    Chalmers University of Technology.
    Händel, Peter
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. ACCESS Linnaeus Centre, Signal Processing Lab, KTH Royal Institute of Technology.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Behavioral Modeling and Linearization of Crosstalk and Memory Effects in RF MIMO Transmitters2014In: IEEE transactions on microwave theory and techniques, ISSN 0018-9480, E-ISSN 1557-9670, Vol. 62, no 4, p. 810-823Article in journal (Refereed)
    Abstract [en]

    This paper proposes three novel models for behavioral modeling and digital pre-distortion (DPD) of nonlinear 2$,times,$ 2 multiple-input multiple-output (MIMO) transmitters in the presence of crosstalk. The proposed models are extensions of the single-input single-output generalized memory polynomial model. Three types of crosstalk effects were studied and characterized as linear, nonlinear, and nonlinear & linear crosstalk. A comparative study was performed with previously published models for the linearization of crosstalk in a nonlinear 2 $,times,$2 MIMO transmitter. The experiments indicate that, depending on the type of crosstalk, the selection of the correct model in the transmitter is necessary for behavioral modeling and sufficient DPD performance. The effects of coherent and partially noncoherent signal generation on the performance of DPD were also studied. For crosstalk levels of ${-}{hbox{30}}$ dB, the difference in the normalized mean square error and adjacent channel power ratio was found to be 3–4 dB between coherent and partially noncoherent signal generation.

  • 187.
    Amin, Shoaib
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. KTH, Signalbehandling.
    Landin, Per N.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Händel, Peter
    KTH, Signalbehandling.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    2D Extended envelope memory polynomial model for concurrent dual-band RF transmitters2017In: International journal of microwave and wireless technologies, ISSN 1759-0795, E-ISSN 1759-0787, Vol. 9, no 8, p. 1619-1627Article in journal (Refereed)
    Abstract [en]

    The paper presents a 2D extended envelope memory polynomial (2D-EEMP) model for concurrent dual-band radio frequency (RF) power amplifiers (PAs). The model is derived based on the physical knowledge of a dual-band RF PA. The derived model contains cross-modulation terms not included in previously published models; these terms are found to be of importance for both behavioral modeling and digital pre-distortion (DPD). The performance of the derived model is evaluated both as the behavioral model and DPD, and the performance is compared with state-of-the-art2D-DPD and dual-band generalized memory polynomial (DB-GMP) models. Experimental result shows that the proposed model resulted in normalized mean square error (NMSE) of -51.7/-51.6dB and adjacent channel error power ratio (ACEPR) of -63.1/-63.4 dB, for channel 1/2, whereas the 2D-DPD resulted in the largest model error and DB-GMP resulted in model parameters that are 3 times more than those resulted with the proposed model with the same performance. As pre-distorter, the proposed model resulted in adjacent channel power ratio (ACPR) of -55.8/ -54.6 dB for channel 1/2 and is 7-10 dB lower than those resulted with the 2D-DPD model and2-4 dB lower compared to the DB-GMP model.

  • 188.
    Amin, Shoaib
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics. KTH, Signalbehandling.
    Van Moer, Wendy
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Händel, Peter
    Department of Signal Processing, KTH 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.
    Characterization of concurrent dual-band power amplifiers using a dual two-tone excitation signal2015In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 64, no 10, p. 2781-2791, article id 7104121Article in journal (Refereed)
    Abstract [en]

    A method to characterize the memory effects in a nonlinear concurrent dual-band transmitter is presented. It is an extension of the conventional two tone test for power amplifiers to concurrent dual band transmitters. The output signal of a concurrent dual-band transmitter is affected not only by intermodulation products but also by cross-modulation products. In one frequency band, the transmitter is excited by a two tone signal which frequency separation is swept. In the second band the transmitter is concurrently excited by an other two tone signal with slightly wider frequency separation. The frequency difference of the two signals is fixed during the frequency sweep. The two tone test is made at different power levels. The upper and lower third-order inter- and cross-modulation products are measured. The asymmetry between the upper and lower third-order inter- and cross-modulation products are measures of the transmitter's memory effects. The measurement results show that the memory effects are more dominant in the third-order intermodulation products than in the cross modulation products. An error analysis and system calibration was performed and measurement results for two different devices are presented.

  • 189.
    Amin, Shoaib
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Van Moer, Wendy
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Händel, Peter
    Department of Information Science and Engineering, KTH 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.
    Rebuttal to "On Dual-Band Amplifications Using Dual Two-Tones Clarifications and Discussions"2017In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 66, no 10, p. 2795-2797Article in journal (Refereed)
    Abstract [en]

    This rebuttal is to "€œOn dual-band amplifications using dual two-tone: Clarifications and discussion". In the following, we provide our reply.

  • 190.
    Amin, Shoaib
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Zenteno, Efrain
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Landin, Per
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Isaksson, Magnus
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Händel, Peter
    ACCESS Linnaeus Centre, Signal Processing Lab, KTH Royal Institute of Technology.
    Noise Impact on the Identification of DigitalPredistorter Parameters in the Indirect LearningArchitecture2012In: 2012 Swedish Communication Technologies Workshop (Swe-CTW), IEEE conference proceedings, 2012, p. 36-39Conference paper (Refereed)
    Abstract [en]

    The indirect learning architecture (ILA) is the mostused methodology for the identification of Digital Pre-distorter(DPD) functions for nonlinear systems, particularly for highpower amplifiers. The ILA principle works in black box modelingrelying on the inversion of input and output signals of thenonlinear system, such that the inverse is estimated. This paperpresents the impact of disturbances, such as noise in the DPDidentification. Experiments were performed with a state-of-artDoherty power amplifier intended for base station operationin current telecommunication wireless networks. As expected,a degradation in the performance of the DPD (measured innormalized mean square error (NMSE)) is found in our experiments.However, adjacent channel power ratio (ACPR) canbe a misleading figure of merit showing improvement in theperformance for wrongly estimated DPD functions.

  • 191.
    Amiri, Shahnaz
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy engineering. Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Energisystem.
    Economic and Environmental Benefits of CHP-based District Heating Systems in Sweden2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Future energy systems and thus the climate are affected by many factors, such as energy resources, energy demand, energy policy and the choice of energy technologies. Energy systems of the future are facing three main challenges; the steady growth of global energy demand, the energy resource depletion, as well as the increasing emissions of carbon dioxide (CO2) and other greenhouse gases and their impact on climate change. To meet the mentioned challenges with sustainability in mind, actions that increase energy efficiency and choosing an energy-efficient energy system which is cost efficient will be essential. Combined heat and power (CHP) plants and district heating and cooling could contribute greatly to increased system efficiency by using energy otherwise wasted.

    The aim of this study is to increase the understanding of how CHP-based district heating and cooling systems using different primary energy sources can contribute to more cost-efficient energy systems, which reduce global CO2 emissions, and to highlight the impact of some important parameters and measures on Swedish municipal district heating systems. An important assumption in this study is the estimation of CO2 emissions from electricity production, which is based on marginal electricity perspectives. In the short term, the marginal electricity is assumed to come from coal-fired condensing power plants while in the long term it consists of electricity produced by natural gas-fired combined cycle condensing power plants. This means that the local electricity production will replace the marginal electricity production. The underlying assumption is an ideal fully deregulated European electricity market where trade barriers are removed and there are no restrictions on transfer capacity.

    The results show that electricity generation in CHP plants, particularly in higher efficiency combined steam and gas turbine heat and power plants using natural gas, can reduce the global environmental impact of energy usage to a great extent. The results confirm, through the scenarios presented in this study, that waste as a fuel in CHP-based district heating systems is fully utilised since it has the lowest operational costs. The results also show how implementation of a biogas-based CHP plant in a biogas system contributes to an efficient system, as well as lowering both CO2 emissions and system costs. The results show that replacing electricity-driven (e.g. compression) cooling by heat-driven cooling using district heating (e.g. absorption chillers) in a CHP system is a cost-effective and climate friendly technology as electricity consumption is reduced while at the same time the electricity generation will be increased. The results of the study also show that there is potential to expand district heating systems to areas with lower heat density, with both environmental and economic benefits for the district heating companies.

    The results reveal that the operation of a studied CHP-based district heating system with an imposed emission limit is very sensitive to the way CO2 emissions are accounted, i.e., local CO2 emissions or emissions from marginal electricity production. The results show how the electricity production increases in the marginal case compared with the local one in order to reduce global CO2 emissions. The results also revealed that not only electricity and fuel prices but also policy instruments are important factors in promoting CHP-based district heating and cooling systems. The use of electricity certificates has a large influence for the introduction of biogas-based cogeneration. Another conclusion from the modelling is that present Swedish policy instruments are strong incentives for cogeneration with similar impact as applying external costs.

  • 192.
    Amiri, Shahnaz
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy engineering. Department of Management and Engineering, Division of Energy Systems, Linköping University, Linköping, Sweden.
    Henning, Dag
    Optensys Energianalys, Linköping, Sweden .
    Karlsson, Björn G.
    Department of Management and Engineering, Division of Energy Systems, Linköping University, Linköping, Sweden .
    Simulation and introduction of a CHP plant in a Swedish biogas system2013In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 49, p. 242-249Article in journal (Refereed)
    Abstract [en]

    The objectives of this study are to present a model for biogas production systems to help achieve a more cost-effective system, and to analyse the conditions for connecting combined heat and power (CHP) plants to the biogas system. The European electricity market is assumed to be fully deregulated. The relation between connection of CHP. increased electricity and heat production, electricity prices, and electricity certificate trading is investigated. A cost-minimising linear programming model (MODEST) is used. MODEST has been applied to many energy systems, but this is the first time the model has been used for biogas production. The new model, which is the main result of this work, can be used for operational optimisation and evaluating economic consequences of future changes in the biogas system. The results from the case study and sensitivity analysis show that the model is reliable and can be used for strategic planning. The results show that implementation of a biogas-based CHP plant result in an electricity power production of approximately 39 GW h annually. Reduced system costs provide a profitability of 46 MSEK/year if electricity and heat prices increase by 100% and electricity certificate prices increase by 50%. CO2 emission reductions up to 32,000 ton/year can be achieved if generated electricity displaces coal-fired condensing power.

  • 193.
    Amiri, Shahnaz
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy engineering.
    Moshfegh, Bahram
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy engineering.
    Possibilities and consequences of deregulation of the European electricity market for connection of heat sparse areas to district heating systems2010In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 87, no 7, p. 2401-2410Article in journal (Refereed)
    Abstract [en]

    The objective of the study is to analyse the conditions for connection of residential buildings in heat sparse areas to district heating systems in order to increase electricity production in municipal combined heat and power plants. The European electricity market has been assumed to be fully deregulated. The relation between connection of heat sparse areas, increased electricity and heat production as well as electricity prices, fuel prices and emissions rights is investigated. The results of the study show that there is potential to expand the district heating market to areas with lower heat concentrations in the cities of Gavle, Sandviken and Borlange in Sweden, with both economic and environmental benefits. The expansion provides a substantial heat demand of approximately 181 GWh/year, which results in an electricity power production of approximately 43 GWh/year. Since the detached and stand-alone houses in the studied heat sparse areas have been heated either by oil boiler or by direct electricity, connection to district heating also provides a substantial reduction in emissions of CO(2). The largest reductions in CO(2) emissions are found to be 211 ktonnes/year assuming coal-fired condensing power as marginal electricity production. Connection of heat sparse areas to district heating decrease the system costs and provide a profitability by approximately 22 million EURO/year for the studied municipalities if the price of electricity is at a European level, i.e. 110 EURO/MWh. Sensitivity analysis shows, among other things, that a strong relation exists between the price of electricity and the profitability of connecting heat sparse areas to district heating systems.

  • 194.
    Amiri, Shahnaz
    et al.
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för energi- och maskinteknik. Department of Management and Engineering, Division of Energy Systems, Linköping University, Linköping, Sweden.
    Trygg, Louise
    Department of Management and Engineering, Division of Energy Systems, Linköping University, Linköping, Sweden.
    Moshfegh, Bahram
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för energi- och maskinteknik. Department of Management and Engineering, Division of Energy Systems, Linköping University, Linköping, Sweden.
    Assessment of the natural gas potential for heat and power generation in the County of Östergötland in Sweden2009In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 37, no 2, p. 496-506Article in journal (Refereed)
    Abstract [en]

    The aim of this study is to investigate the potential use of natural gas for heat and power production for the municipality of Linkoping, Norrkoping and Finspang in the County of Ostergotland, Sweden. The results of the study revealed that these three municipalities with the present heating demand can convert 2030 GWh/year of the present fuel mixed to natural gas. The expansion of natural gas provides the possibility to increase the electricity generation with approximately 800 GWh annually in the County of Ostergotland. The global emissions of CO(2) reduce also by approximately 490 ktonne/year by assuming the coal condensing power plant as the marginal power plant. The total system cost decreases by 76 Mkr/year with the present electricity price which varies between 432 and 173 SEK/MWh and with 248 Mkr/year if the present electricity price increases to 37% which is approximately corresponding to European electricity prices. Sensitivity analysis is done with respect to the different factors such as price of electricity, natural gas, etc. The findings show that increased price of electricity and increased district heating demand increases the profitability to convert to natural gas using CHP plant. (C) 2008 Elsevier Ltd. All rights reserved.

  • 195.
    Amiri, Shahnaz
    et al.
    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, Linköping, Sweden.
    Weinberger, Gottfried
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Increased cogeneration of renewable electricity through energy cooperation in a Swedish district heating system - A case study2018In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 116, p. 866-877Article in journal (Refereed)
    Abstract [en]

    The present study of the district heating (DH) system in the city of Kisa, Sweden, shows how, through energy cooperation with a nearby sawmill and paper mill, a local energy company contributes to energy-efficient DH and cost-effective utilization of a new biofuel combined heat and power (CHP) plant. Cases of stand-alone and integrated energy systems are optimized with the linear program MODEST. The European power market is assumed to be fully deregulated. The results show clear advantages for the energy company to cooperate with these industries to produce heat for DH and process steam for industry. The cooperating industries gain advantages from heat and/or biofuel by-product supply as well. The opening to use a biofuel CHP plant for combined heat supply results in cogenerated electricity of almost 29 GWh/a with an increased biofuel use of 13 GWh/a, zero fuel oil use and CO2 emission reductions of 25,800 tons CO2/a with coal-condensing power plant on the margin and biofuel as limited resource. The total system cost decreases by −2.18 MEUR/a through extended cooperation and renewable electricity sales. The sensitivity analysis shows that the profitability of investing in a biofuel CHP plant increases with higher electricity and electricity certificate prices.

  • 196.
    Ammert, Niklas
    et al.
    Faculty of Arts and Humanities, Linnaeus University, Sweden.
    Edling, Silvia
    University of Gävle, Faculty of Education and Business Studies, Department of Educational sciences, Educational science.
    Löfstrom, Jan
    History and Social Studies Education, University of Helsinki, Finland.
    Sharp, Heather
    School of Education, University of Newcastle, Australia.
    Bridging historical consciousness and moral consciousness: promises and Challenges2017In: Historical Encounters: A journal of historical consciousness, historical cultures and history education, E-ISSN 2203-7543, Vol. 4, no 1, p. 1-13Article in journal (Refereed)
    Abstract [en]

    This special issue is the result of the workshop, Towards an integrated theory ofhistorical and moral consciousness, supported by Riksbankens Jubileumsfond (The SwedishFoundation for Humanities and Social Sciences) and Suomen kasvatuksen ja koulutuksen historianseura (The Finnish Society for the History of Education) and held at the University of Helsinki, in2015. History teaching and social studies education are increasingly expected to develop, amongother things, students’ historical consciousness. This goal is highly relevant for students’ ability todeal constructively with controversial issues of history which is an important civic competence inthe situation where in many societies’ political arguments concerning, for example, citizenshiprights, ethnic and cultural diversity, and democracy are only too often fuelled by simplistic narrativesof historical change and continuity. However, there is a blank spot in the existing research onhistorical consciousness in that intersections between historical and moral consciousness remainvery much unexplored. This special issue seeks to identify promising theoretical and conceptualpoints of convergence for future interdisciplinary studies of historical and moral consciousness.Contributors are from the fields of history, educational research, social psychology, and philosophy.

  • 197.
    Ammert, Niklas
    et al.
    Linnéuniversitet.
    Löfström, Jan
    Helsingfors universitet.
    Edling, Silvia
    University of Gävle, Faculty of Education and Business Studies, Department of Educational sciences, Educational science, Curriculum studies.
    Sharp, Heather
    Newcastle University, Australia.
    Identifying aspects of temporal orientation in students’ moral reflections2019Conference paper (Refereed)
  • 198.
    Andersen, Niklas
    et al.
    Energi Funktion Komfort Skandinavien AB, Nacka, Sweden.
    Eriksson, Ola
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Hillman, Karl
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Wallhagen, Marita
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Wind turbines’ end-of-life: Quantification and characterisation of future waste materials on a national level2016In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 9, no 12, article id 999Article in journal (Refereed)
    Abstract [en]

    Globally, wind power is growing fast and in Sweden alone more than 3000 turbines have been installed since the mid-1990s. Although the number of decommissioned turbines so far is few, the high installation rate suggests that a similarly high decommissioning rate can be expected at some point in the future. If the waste material from these turbines is not handled sustainably the whole concept of wind power as a clean energy alternative is challenged. This study presents a generally applicable method and quantification based on statistics of the waste amounts from wind turbines in Sweden. The expected annual mean growth is 12% until 2026, followed by a mean increase of 41% until 2034. By then, annual waste amounts are estimated to 240,000 tonnes steel and iron (16% of currently recycled materials), 2300 tonnes aluminium (4%), 3300 tonnes copper (5%), 340 tonnes electronics (<1%) and 28,000 tonnes blade materials (barely recycled today). Three studied scenarios suggest that a well-functioning market for re-use may postpone the effects of these waste amounts until improved recycling systems are in place.

  • 199.
    Andersen, O.
    et al.
    Ericsson AB.
    Wisell, David
    Ericsson AB.
    Keskitalo, Niclas
    University of Gävle, Center for RF Measurement Technologies. University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för elektronik.
    Measurement of ACLR with high dynamic range2008In: IEEE MTT-S International Microwave Symposium Digest, Atlanta, GA, 2008, p. 273-277Conference paper (Other academic)
    Abstract [en]

    In this paper a method to overcome the insufficient dynamic range of RF measurement instruments, i.e. signal generators and spectrum analyzers, for distortion measurements on feedforward and other highly linear amplifiers, is discussed. A circuit board is designed, built and verified. Its performance is found to be superior to traditional methods using filters, both from a technical performance and flexibility standpoint as well as from an economic view. ACLR measurements for WCDMA signals can be done well below -70 dBc using the produced circuit board. © 2008 IEEE.

  • 200.
    Andersen, Olav
    et al.
    Ericsson.
    Björsell, Niclas
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för elektronik. University of Gävle, Center for RF Measurement Technologies.
    Keskitalo, Niclas
    University of Gävle, Center for RF Measurement Technologies. University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för elektronik.
    A Test-Bed Designed to Utilize Zhu’s General Sampling Theorem to Characterize Power Amplifiers2009In: Instrumentation and measurement technology conference 2009 I2MTC '09 IEEE, Singapore, 2009, p. 201-204Conference paper (Refereed)
    Abstract [en]

    Characterizing power amplifiers require test set-ups with performance superior to the power amplifiers. A commonly used method is to use an IQ-demodulator. However, problem arises due to imperfections in the demodulator such as IQ-imbalance; an alternative method is to use a direct down converter to intermediate frequency. The drawback then is the limited bandwidth. However, the required bandwidth of the ADC does not need to be exceptional. According to Zhu’s general sampling theorem is it enough to sample the output signal at the Nyquist rate of the input. However, even though the required sampling rate is reduced the demands on the analog bandwidth remains. Unfortunately, commercially available instruments such as vector signal analyzers can not be used for this purpose since their analog bandwidth is too small. In this paper a test-bed is designed to utilize the Zhu’s general sampling theorem. The RF front-end has frequency range of 500 MHz – 2.7 GHz and a bandwidth of 1 GHz. All performance data are verified with measurements.

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