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  • 1. A, Ahmad
    et al.
    G, Bianchi
    L, Bernstein
    G, Fodor
    G, Pujolle
    LB, Sung
    YD, Yao
    QoS support and service differentiation in wireless networks2004Ingår i: International Journal of Communication Systems, ISSN 1074-5351, E-ISSN 1099-1131, Vol. 17, nr 6, s. 507-512Artikel i tidskrift (Refereegranskat)
  • 2.
    A Asif, Farazee M
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Circular Manufacturing Systems: A development framework with analysis methods and tools for implementation2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The society today lives on the philosophy of ‘take-make-use-dispose.’ In the long run, this is not sustainable as the natural resources and the waste carrying capacity of the earth are limited. Therefore, it is essential to reduce dependency on the natural resources by decoupling the growth from the consumption. In this venture, both the society and the manufacturing industry have a vital role to play. The society needs to shift towards Circular Economy that rests upon the philosophy of ‘take-make-use-reuse’ and the manufacturing industry has to be a major stakeholder in this shift. Despite being proven to be both economically and environmentally beneficial, successful examples of circular systems are few today. This is primarily due to two reasons; firstly, there is a lack of systemic and systematic approach to guide industries and secondly, there is a lack of analysis methods and tools that are capable of assessing different aspects of circular manufacturing systems. Taking on to these challenges, the objective of this research is to bring forward a framework with methods and decision support tools that are essential to implement circular manufacturing systems. The initial conceptual framework with the systemic approach is developed based on extensive review and analysis of research, which is further adapted for industrial implementation. Systematic analysis methods, decision support and implementation tools are developed to facilitate this adaptation. This development has been supported by four cases from diverse manufacturing sectors. Behind each decision support tool, there are analysis methods built upon mainly system dynamics principles. These tools are based on simulation platforms called Stella and Anylogic. Among other things, these tools are capable of assessing the performance of closed-loop supply chains, consequences of resource scarcity, potential gains from resource conservation and overall economic and environmental performance of circular manufacturing systems.

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  • 3.
    A Asif, Farazee M
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Rashid, Amir
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Bianchi, Carmine
    University of Palermo (ITALY) Faculty of Political Sciences - Department of International Studies .
    Nicolescu, Mihai
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion, Maskin- och processteknologi.
    Performance analysis of the closed loop supply chain2012Ingår i: Journal of Remanufacturing, ISSN 2210-4690, Vol. 2, nr 4Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose

    The question of resource scarcity and emerging pressure of environmental legislations has brought a new challenge for the manufacturing industry. On the one hand, there is a huge population that demands a large quantity of commodities; on the other hand, these demands have to be met by minimum resources and pollution. Resource conservative manufacturing (ResCoM) is a proposed holistic concept to manage these challenges. The successful implementation of this concept requires cross functional collaboration among relevant fields, and among them, closed loop supply chain is an essential domain. The paper aims to highlight some misconceptions concerning the closed loop supply chain, to discuss different challenges, and in addition, to show how the proposed concept deals with those challenges through analysis of key performance indicators (KPI).

    Methods

    The work presented in this paper is mainly based on the literature review. The analysis of performance of the closed loop supply chain is done using system dynamics, and the Stella software has been used to do the simulation. Findings The results of the simulation depict that in ResCoM; the performance of the closed loop supply chain is much enhanced in terms of supply, demand, and other uncertainties involved. The results may particularly be interesting for industries involved in remanufacturing, researchers in the field of closed loop supply chain, and other relevant areas. Originality The paper presented a novel research concept called ResCoM which is supported by system dynamics models of the closed loop supply chain to demonstrate the behavior of KPI in the closed loop supply chain.

  • 4.
    A Atlasov, Kirill
    et al.
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    Felici, Marco
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    Karlsson, Fredrik
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Halvledarmaterial. Linköpings universitet, Tekniska högskolan.
    Gallo, Pascal
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    Rudra, Alok
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    Dwir, Benjamin
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    Kapon, Eli
    Ecole Polytech Fed Lausanne, Lab Phys Nanostruct, CH-1015 Lausanne, Switzerland .
    1D photonic band formation and photon localization in finite-size photonic-crystal waveguides2010Ingår i: OPTICS EXPRESS, ISSN 1094-4087, Vol. 18, nr 1, s. 117-122Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A transition from discrete optical modes to 1D photonic bands is experimentally observed and numerically studied in planar photonic-crystal (PhC) L-N microcavities of length N. For increasing N the confined modes progressively acquire a well-defined momentum, eventually reconstructing the band dispersion of the corresponding waveguide. Furthermore, photon localization due to disorder is observed experimentally in the membrane PhCs using spatially resolved photoluminescence spectroscopy. Implications on single-photon sources and transfer lines based on quasi-1D PhC structures are discussed.

  • 5.
    A Elhassan, Amro
    KTH, Skolan för elektro- och systemteknik (EES).
    Building automation and control2012Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
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  • 6. A, Eriksson
    et al.
    G, Fodor
    A middlebox control plane framework for wireless and mobile IP networks2004Ingår i: 2004 International Conference on Parallel Processing Workshops, 2004 (ICPP 2004 Workshops) / [ed] IEEE, New York: IEEE conference proceedings, 2004, s. 322-329Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    In wireless and mobile IP networks there is a need to support a set of functions that are related to wireless QoS provisioning, resource optimizations, mobility and security management and operator policy enforcement. These requirements have lead to the frequent usage of so called middleboxes including header/payload compressors, performance enhancement proxies, tunnel endpoints, packet filters and redirectors, QoS schedulers and others. Unfortunately, the increasing usage of these types of devices often leads to undesirable artifacts called feature interactions. In this paper we propose a framework that aims to coordinate the operation of middleboxes such that feature interactions are avoided. The three main ideas are (1) the separation of the control plane from the distributed network nodes, (2) the usage of a middlebox function independent horizontal protocol that allows mobile hosts to communicate their desired service requests to the network and (3) the usage of a vertical protocol between the network control and user planes. We present two examples in which this framework helps eliminate the risk for feature interactions. We comment on the relationship between the end-to-end principle and this framework. Finally, we discuss how future middleboxes can fit into this framework.

  • 7.
    A, Fredrik
    et al.
    KTH, Skolan för elektro- och systemteknik (EES).
    Forsberg, A
    KTH, Skolan för elektro- och systemteknik (EES).
    Forsén, Tobias
    KTH, Skolan för elektro- och systemteknik (EES).
    Tracking Using Wireless Camera Networks2015Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
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  • 8.
    A Herrera, I
    et al.
    Norwegian University Science and Technology NTNU.
    Woltjer, Rogier
    Linköpings universitet, Institutionen för datavetenskap, CSELAB - Cognitive Systems Engineering Laboratory. Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system.
    Comparing a multi-linear (STEP) and systemic (FRAM) method for accident analysis2010Ingår i: RELIABILITY ENGINEERING and SYSTEM SAFETY, ISSN 0951-8320, Vol. 95, nr 12, s. 1269-1275Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Accident models and analysis methods affect what accident investigators look for, which contributory factors are found, and which recommendations are issued. This paper contrasts the Sequentially Timed Events Plotting (STEP) method and the Functional Resonance Analysis Method (FRAM) for accident analysis and modelling. The main issue addressed in this paper is the comparison of the established multi-linear method STEP with the new systemic method FRAM and which new insights the latter provides for accident analysis in comparison to the former established multi-linear method. Since STEP and FRAM are based on a different understandings of the nature of accidents, the comparison of the methods focuses on what we can learn from both methods, how, when, and why to apply them. The main finding is that STEP helps to illustrate what happened, involving which actors at what time, whereas FRAM illustrates the dynamic interactions within socio-technical systems and lets the analyst understand the how and why by describing non-linear dependencies, performance conditions, variability, and their resonance across functions.

  • 9. A. Hosseini, V.
    et al.
    Karlsson, L.
    Örnek, Cem
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap. Swerea KIMAB AB.
    Reccagni, P.
    Wessman, S.
    Engelberg, D.
    Microstructure and functionality of a uniquely graded super duplex stainless steel designed by a novel arc heat treatment method2018Ingår i: Materials Characterization, ISSN 1044-5803, E-ISSN 1873-4189, Vol. 139, s. 390-400Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A novel arc heat treatment technique was applied to design a uniquely graded super duplex stainless steel (SDSS), by subjecting a single sample to a steady state temperature gradient for 10 h. A new experimental approach was used to map precipitation in microstructure, covering aging temperatures of up to 1430 °C. The microstructure was characterized and functionality was evaluated via hardness mapping. Nitrogen depletion adjacent to the fusion boundary depressed the upper temperature limit for austenite formation and influenced the phase balance above 980 °C. Austenite/ferrite boundaries deviating from Kurdjumov–Sachs orientation relationship (OR) were preferred locations for precipitation of σ at 630–1000 °C, χ at 560–1000 °C, Cr2N at 600–900 °C and R between 550 °C and 700 °C. Precipitate morphology changed with decreasing temperature; from blocky to coral-shaped for σ, from discrete blocky to elongated particles for χ, and from polygonal to disc-shaped for R. Thermodynamic calculations of phase equilibria largely agreed with observations above 750 °C when considering nitrogen loss. Formation of intermetallic phases and 475 °C-embrittlement resulted in increased hardness. A schematic diagram, correlating information about phase contents, morphologies and hardness, as a function of exposure temperature, is introduced for evaluation of functionality of microstructures.

  • 10.
    A. M. Naiini, Maziar
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Horizontal Slot Waveguides for Silicon Photonics Back-End Integration2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This thesis presents the development of integrated silicon photonic devices. These devices are compatible with the present and near future CMOS technology. High-khorizontal grating couplers and waveguides are proposed. This work consists of simulations and device design, as well as the layout for the fabrication process, device fabrication, process development, characterization instrument development and electro-optical characterizations.

    The work demonstrates an alternative solution to costly silicon-on-insulator photonics. The proposed solution uses bulk silicon wafers and thin film deposited waveguides. Back-end deposited horizontal slot grating couplers and waveguides are realized by multi-layers of amorphous silicon and high-k materials.

    The achievements of this work include: A theoretical study of fully etched slot grating couplers with Al2O3, HfO2 and AIN, an optical study of the high-k films with spectroscopic ellipsometry, an experimental demonstration of fully etched SiO2 single slot grating couplers and double slot Al2O3 grating couplers, a practical demonstration of horizontal double slot high-k waveguides, partially etched Al2O3 single slot grating couplers, a study of a scheme for integration of the double slot Al2O3  waveguides with selectively grown germanium PIN photodetectors, realization of test chips for the integrated germanium photodetectors, and study of integration with graphene photodetectors through embedding the graphene into a high-k slot layer.

    From an application point of view, these high-k slot waveguides add more functionality to the current silicon photonics. The presented devices can be used for low cost photonics applications. Also alternative optical materials can be used in the context of this photonics platform.

    With the robust design, the grating couplers result in improved yield and a more cost effective solution is realized for integration of the waveguides with the germanium and graphene photodetectors.

     

     

     

     

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    Thesis
  • 11.
    A Monfared, Behzad
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Tillämpad termodynamik och kylteknik.
    Design and Construction of a Small Ammonia Heat Pump2010Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In view of the fact that most of the synthetic refrigerants, in case of leakage or release, are harmful to the environment by contributing in global warming or depleting stratospheric ozone layer, many research works have been done recently to find alternative refrigerants posing no or negligible threat to the environment. Among alternative refrigerants, ammonia, a natural refrigerant with zero Global Warming Potential (GWP) and Ozone Depletion Potential (ODP), can be a sensible choice.Although ammonia has been used for many years in large industrial systems, its application in small units is rare. In this project a small heat pump with about 7 kW heating capacity at -5 °C and +40 °C evaporation and condensation temperatures is designed and built to work with ammonia as refrigerant. The heat pump is expected to produce enough heat to keep a single-family house warm in Sweden and to provide tap hot water for the house. After successful completion of this project, it is planned to install the heat pump in a house to test it throughout a heating season to study its performance in real working conditions.Since ammonia is flammable and toxic in high concentrations, the refrigerant charge is tried to be kept low in the heat pump to reduce the risk of fire or poisoning in case of unwanted release of refrigerant to the surroundings. The compact design of the heat pump helps reducing the refrigerant charge. Besides, considering the limited space normally reserved for installation of a heat pump in a house, the compact design of the heat pump is necessary.

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    B A Monfared 2010_Design and Construction of a Small Ammonia Heat Pump_MSc Thesis
  • 12.
    A Monfared, Behzad
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Tillämpad termodynamik och kylteknik.
    Magnetic Refrigeration for Near Room-Temperature Applications2018Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Kylning spelar en avgörande roll i många olika sektorer och förbrukar cirka 17 % av den elektricitet som produceras globalt. Kylprocessernas energiförbrukning utgör alltså en stor andel av primärenergiförbrukningen och innebär även annan miljöpåverkan. Förutom miljöpåverkan som är förknippad med energiförbrukningen bidrar ångkompressionssystemen till global uppvärmning på grund av utsläpp av köldmedier i atmosfären. Som en alternativ teknik för nära rumstemperaturapplikationer föreslås magnetisk kylning av vissa forskare, för att eliminera utsläpp av köldmedier i atmosfären och för att minska energiförbrukningen. Denna avhandling är en sammanställning av ett antal studier om magnetisk kylning för rumstemperaturapplikationer.

    I den första studien undersöktes de miljöpåverkningar som är förknippade med magnetisk kylning noggrant genom en livscykelanalys. Livscykelanalysen indikerar att minskningen av miljöpåverkan inte garanteras genom att byta till den magnetiska kylprocessen på grund av de miljöbelastningar som är relaterade till de sällsynta jordartsmetaller som används i magnetisk kylning. För att undvika de extra miljöpåverkningarna bör de magnetiska kylsystemen använda så lite magnetiska material som möjligt, vilket kräver en optimerad design. Dessutom är energieffektivare drift jämfört med ångkompressionssystemen nödvändigt för att få miljöfördelar, åtminstone i vissa miljöpåverkanskategorier.

    En praktisk metod för att optimera designen av magnetiska kylsystem, för att uppnå t.ex. en kompakt design eller hög effektivitet, är användning av en flexibel mjukvarumodell, som simulerar effekten av olika parametrar på systemets prestanda. En sådan mjukvarumodell av det magnetiska kylsystemet har utvecklats och validerats i detta projekt. Ett syfte med utvecklingen av modellen är att öka precisionen av de simulerade resultaten genom att ta hänsyn till mer detaljer än i tidigare modeller. Detta mål uppnås genom ett innovativt sätt att modellera den parasitära värmeöverföringen och inkludera effekten av närvaron av magnetokaloriska material på styrkan av fältet som skapas av magnetaggregatet. Dessutom görs vissa modifieringar eller korrigeringar i de befintliga korrelationerna för att inkludera effekten av bindemedel som används i vissa aktiva magnetiska regeneratorer. Validering av den utvecklade mjukvarumodellen görs med hjälp av experimentella resultat som erhållits från den prototyp som finns vid Institutionen för Energiteknik, Kungliga Tekniska Högskolan.

    En av parametrarna som kan modifieras i den utvecklade mjukvarumodellen är valet av magnetokaloriska material för varje skikt i en skiktad aktiv magnetisk regenerator. Användning av mjukvarumodellen för att optimera valet av material för skikten visar att material med kritiska temperaturer som är lika med den cykliska genomsnittstemperaturen hos de skikt där de används inte nödvändigtvis resulterar i önskad optimal prestanda. Dessutom behövs olika materialval för skikten för att maximera modellernas resultat avseende energieffektivitet eller temperaturskillnaden som erhålls mellan de två ändarna av regeneratorerna. Därför är valet av kritiska temperaturer för skiktens material en ytterligare parameter som ska optimeras i studier med avsikt att förbättra ett systems prestanda.

    Prototypen vid Institutionen för Energiteknik, Kungliga Tekniska Högskolan, var ursprungligen designad för att ersätta ångkompressionssystemet för ett restaurangkylskåp. Det kunde emellertid inte uppfylla de krav för vilka det ursprungligen utformats. Den ovan nämnda utvecklade simuleringsmodellen används för att undersöka hur mycket prestandan kan förbättras genom att förändra valet av material, partikelstorleken, antalet skikt, driftsfrekvensen och flödeshastigheten av värmeöverföringsvätskan. Med andra ord undersöks utrymmet för förbättring av prestandan utan att genomföra stora förändringar i systemet, såsom förändringar i regeneratorers geometri och i magnetaggregatet. Under processen undersöks effekten av bindemedel på prestanda och begränsningar som är förknippade med bindemedlets egenskaper. Trots detta kunde studien inte visa att de ursprungliga målen för prototypen kan uppnås utan att ändra regeneratorernas geometri och de befintliga magnetokaloriska materialen.

    I nästa studie övervägs mer flexibla val av regeneratorernas geometrier och magnetokaloriska material. I den här studien undersöks hur mycket de magnetokaloriska materialen måste förbättras för att magnetiska kylsystem ska kunna konkurrera med ångkompressionssystem vad gäller prestanda. För de två undersökta fallen är de magnetfältberoende egenskaperna hos befintliga materialen tillräckliga förutsatt att vissa andra problem, såsom låg mekanisk stabilitet och inhomogenitet hos egenskaperna, löses. Emellertid, för mer krävande designkriterier, såsom att ge stor kylkapacitet över en betydande temperaturdifferens samtidigt som de magnetiska materialen används sparsamt, behöver de magnetfältberoende egenskaperna också förbättras.

    Ett mindre undersökt område för magnetisk kylning i rumstemperatur är föremål för en annan studie som ingår i avhandlingen. I denna studie modelleras fasta magnetiska kylsystem med Peltier-element som värmebrytare. Eftersom Peltier-elementen förbrukar elektricitet och pumpar värmen kan de modellerade systemen betraktas som hybrid magnetokalorisk-Peltier-kylsystem. För sådana system modelleras i detalj det transienta beteendet hos Peltier-elementen tillsammans med de magnetokaloriska materialskikten. Den matematiska modellen är lämplig för implementering i programmeringsspråk utan behov av kommersiella modelleringsplattformar. Parametrarna som påverkar det modellerade systemets prestanda är många, och optimering av dem kräver en separat studie. De preliminära optimeringsinsatserna ger emellertid inte lovande resultat. Följaktligen kan fokusering på passiva värmebrytare vara mer fördelaktiga.

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  • 13.
    A. Mouris, Boules
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Teknisk informationsvetenskap.
    Ghauch, Hadi
    Department of COMELEC, Institut Mines-Telecom, Telecom-ParisTech, Paris, 91120, France.
    Thobaben, Ragnar
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Teknisk informationsvetenskap.
    Jonsson, B. Lars G.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Elektroteknisk teori och konstruktion.
    Multi-tone Signal Optimization for Wireless Power Transfer in the Presence of Wireless Communication Links2020Ingår i: IEEE Transactions on Wireless Communications, ISSN 1536-1276, E-ISSN 1558-2248, Vol. 19, nr 5, s. 3575-3590Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we study optimization of multi-tone signals for wireless power transfer (WPT) systems. We investigate different non-linear energy harvesting models. Two of them are adopted to optimize the multi-tone signal according to the channel state information available at the transmitter. We show that a second-order polynomial curve-fitting model can be utilized to optimize the multi-tone signal for any RF energy harvester design. We consider both single-antenna and multi-antenna WPT systems. In-band co-existing communication links are also considered in this work by imposing a constraint on the received power at the nearby information receiver to prevent its RF front end from saturation. We emphasize the importance of imposing such constraint by explaining how inter-modulation products, due to saturation, can cause high interference at the information receiver in the case of multi-tone signals. The multi-tone optimization problem is formulated as a non-convex linearly constrained quadratic program. Two globally optimal solution approaches using mixed-integer linear programming and finite branch-and-bound techniques are proposed to solve the problem. The achieved improvement resulting from applying both solution methods to the multi-tone optimization problem is highlighted through simulations and comparisons with other solutions existing in the literature.

  • 14.
    A. Mouris, Boules
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Teknisk informationsvetenskap.
    Kolitsidas, Christos
    Ericsson, Systems and Technology-HW Research, Kista, 164 80, Sweden.
    Thobaben, Ragnar
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Teknisk informationsvetenskap.
    A Dual-Polarized Multi-Antenna Structure for Simultaneous Transmission of Wireless Information and Power2019Ingår i: 2019 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting, APSURSI 2019 - Proceedings, IEEE, 2019, s. 1805-1806, artikel-id 8889079Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, a dual-polarized multi-antenna structure is designed at 2.45 GHz with the goal of allowing simultaneous transmission of wireless information and power. Differential feeding was used to minimize the mutual coupling due to radiation leakage in addition to a mushroom-type EBG structure for suppressing the surface waves. Simulation results for the proposed structure show a mutual coupling level lower than -40 dB between the information transmitting antenna and the power transmitting antennas for both polarizations. The isolation level between the antennas is improved by at least 22 dB and 14 dB for the E-plane and H-plane coupling, respectively.

  • 15.
    A. Oliveira, Roger
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    S. Salles, Rafael
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Rönnberg, Sarah K.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Deep Learning for Power Quality with Special Reference to Unsupervised Learning2023Ingår i: 27th International Conference on Electricity Distribution (CIRED 2023), IEEE, 2023, s. 935-939, artikel-id 10417Konferensbidrag (Refereegranskat)
  • 16.
    A. Sani, Negar
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik.
    M-PSK and M-QAM Modulation/Demodulation of UWB Signal Using Six-Port Correlator2010Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Nowadays high speed and high data rate communication are highly demanded. Consequently, wideband and high frequency transmitter and receivers should be designed. New transmitters and receivers should also have low power consumption, simple design and low manufacturing price in order to fulfill manufacturers’ requests for mass production. Having all above specifications, six-port correlator is a proper choice to be used as modulator and demodulator in transmitters and receivers.

    In this thesis the six-port correlator is introduced, modeled and simulated using Advanced Design System (ADS) software. A simple six-port transmitter/receiver system with a line of sight link is modeled and analyzed in BER, path length and noise terms. The modulation in this system is QAM, frequency is 7.5 GHz and symbol rate is 500 Msymbol/s.

    Furthermore two methods are proposed for high frequency and high symbol rate M-PSK and M-QAM modulation using six-port correlator. The 7.5 GHz modulators are modeled and simulated in ADS. Data streams generated by pseudo random bit generator with 1 GHz bandwidth are applied to modulators. Common source field effect transistors (FETs) with zero bias are used as controllable impedance termination to apply baseband data to modulator. Both modulators show good performance in M-PSK and M-QAM modulation.

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  • 17.
    A., Trubetskaya
    et al.
    National University of Ireland Galway.
    G. R., Surup
    University of Agder.
    Forsberg, Fredrik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    T., Attard
    University of York.
    A., Hunt
    Khon Kaen University.
    V., Budarin
    University of York.
    V., Abdelsayed
    National Energy Technology Laboratory.
    D., Shekhawat
    National Energy Technology Laboratory.
    The Effect of Wood Composition and Supercritical CO2 Extraction on the Charcoal Production2019Ingår i: 2019 AIChE Annual Meeting proceedings, American Institute of Chemical Engineers, 2019, artikel-id 552cKonferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    This work demonstrated that the coupling of supercritical carbon dioxide extraction with slow pyrolysis is effective to remove over half of extractives from low quality wood and to generate biochar from remaining solid wood fractions. The high yields of extractives from supercritical carbon dioxide extraction illustrates the potential utilizing of low quality wood as an alternative feedstock for the sustainable production of value-added chemicals. Results showed that supercritical carbon dioxide extraction has neither a strong impact on the physical properties of original wood nor on the yield of solid biochar. These results are promising as they show that the biochar obtained for this renewable feedstock could be used as an alternative to fossil-based coke in applications including ferroalloy industries. Moreover, the heat treatment temperature and supercritical carbon dioxide extraction had a significant impact on the tar yields, leading to the increase in naphthalene, polycyclic aromatic hydrocarbons, aromatic and phenolic fractions with the greater temperature. The differences in gasification reactivity and dielectric properties of solid biochars, composition and yields of liquid products of non-treated pinewood and extracted wood fraction emphasize the impact of supercritical carbon dioxide extraction on the pyrolysis process. 

  • 18.
    A Österman, Sami
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Kumar, Shirish
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Vattenskärning: Teknologin och dess tillämpningsområden2010Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Vattenskärning anses generellt vara en mångsidig bearbetningsteknik med en mängd tillämpningsområden. Ren vattenskärning gör det möjligt att skära i mjuka material som gummi, medan tillsatt abrasivmedel tillåter skärning av bland annat stål och keramik. Skärningen lämnar inga restspänningar eller någon värmepåverkan i materialet. Dessutom blir ytfinheten så bra att man ofta slipper efterbehandling. Processen skapar inte heller några farliga gaser och är relativt miljövänlig. Syftet med detta arbete har varit att undersöka vattenskärningstekniken, dess nuvarande samt nya tillämpningsområden. Målet har även varit att jämföra tekniken med alternativa bearbetningsmetoder för att klargöra för‐ och nackdelar mellan dessa. Detta gjordes i syfte för att undersöka vilken teknik som är lämpligast att använda beroende på egenskaper såsom material, materialtjocklek och storlek av tillverkad serie. Arbetet har skrivits från Sverige och Frankrike och därmed har man valt att undersöka ifall användningsområdena hos vattenskärning skiljer sig mellan de två länderna. För att uppnå syftet valdes tre frågeställningar för att besvara hur man utökar tillämpningsområdet för vattenskärning, vilka för‐ respektive nackdelar vattenskärning har jämfört med andra skärmetoder och hur tillämpningsområdena är annorlunda mellan Frankrike och Sverige. De huvudsakliga informationskällorna för arbetet har varit intervjuer med tillverkande företag som använder sig av vattenskärning, leverantörer av vattenskärningsmaskiner och forskningsinstitut. Teoretisk komplettering har skett i form av informationssamling från litteratur och vetenskapliga artiklar. Valda primärkällor är företagshemsidor hos aktörer inom bearbetningsindustrin. Rapporten visar att vattenskärningstekniken är applicerbar inom ett flertal industrier och att tillämpningsområdena skiljer sig mellan Frankrike och Sverige; i Frankrike används vattenskärning främst inom livsmedelsindustrin, medan den är mer utbredd inom verkstadsindustrin i Sverige. Aktörer på den svenska marknaden är skeptiska till användning av vattentryck på över 400 MPa, trots att det tyder på många fördelar. Den huvudsakliga begränsningen hos vattenskärning är tjockleken hos materialet. Vid skärning av stål över 30 mm kan strålen fördröjas och resultera i en ickeprecis skärning, ett problem som löses genom att ändra skärparametrar såsom skärhastighet eller genom snedställning av skärmunstycket. Efter en utvärdering av plasma‐, laser‐ och vattenskärning, kan man konstatera att ingen metod är direkt konkurrerande med en annan, då varje teknik lämpar sig bäst inom sitt respektive användningsområde. Teknikerna kompletterar snarare än konkurrerar med varandra.

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  • 19.
    Aaboen, Lise
    NTNU, Trondheim.
    BATON-CHANGING ON EGGSHELLS – TRANSFERRING SUPPLIER RELATIONSHIPS WHEN MOVING PRODUCTION2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Production transfers are a result of outsourcing and offshoring decisions. Though, because of

    the strategic focus of the outsourcing literature have not the operational issues of how

    relationship development between sender, receiver and raw material been fully depicted. The

    purpose of the present paper is to explore relationship development connected to transfer of

    raw material supplies responsibility during transfer of production. To fulfil the purpose, four

    different production transfers were studied: three from Sweden to China, Romania and

    Hungary respectively and one transfer from Holland to Sweden. We can see that the

    dependence and power shifts gradually between the sender and the receiver and the

    relationship between them sets the arena for what relationship is developed between the

    receiver and the raw material suppliers. Furthermore, short social distances can over bridge

    cultural and technological distances to some extent, because it motivates to take the

    relationship into a more developed state.

  • 20.
    Aaboen, Lise
    et al.
    Department of Industrial Economics and Technology Management, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.
    Fredriksson, Anna
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    The relationship development aspect of production transfer2016Ingår i: Journal of Purchasing and Supply Management, ISSN 1478-4092, E-ISSN 1873-6505, Vol. 22, nr 1, s. 53-65Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Production transfers are a result of outsourcing and offshoring decisions. Because of the strategic focus of the outsourcing literature, the operational issues of relationship development between sender and receiver and its impact on the transfer progress have not been fully depicted. The purpose of the present paper is to explore relationship development during production transfer. To fulfil this purpose, we studied three different production transfers and derived four propositions for further testing. Our main conclusions included that dependence and power gradually shift between the sender and the receiver and that the relationship between them sets the arena for what types of relationships can be developed between the receiver and the suppliers. Furthermore, short social distances can bridge cultural and technological distances to some extent, because it motivates the actors to bring their relationship into a more developed state. Finally, we noticed that the headquarters’ involvement can work both as an inhibitor as well as a converter.

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  • 21.
    Aaboen, Lise
    et al.
    Norwegian University of Science and Technology .
    La Rocca, Antonella
    BI Norwegian Business School.
    Lind, Frida
    Chalmers University of Technology.
    Perna, Andrea
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Industriell teknik. Universita' Politecnica delle Marche.
    Shih, Tommy
    Starting up in Business Networks: Why relationships matter in entrepreneurship2016 (uppl. 1st)Bok (Refereegranskat)
  • 22.
    Aadland, Reidun C.
    et al.
    NTNU Norwegian University of Science and Technology, Norway.
    Akarri, Salem
    NTNU Norwegian University of Science and Technology, Norway.
    Heggset, Ellinor B
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Material- och ytdesign.
    Syverud, Kristin
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Material- och ytdesign. NTNU Norwegian University of Science and Technology, Norway.
    Torsæter, Ole
    NTNU Norwegian University of Science and Technology, Norway.
    A core flood and microfluidics investigation of nanocellulose as a chemical additive to water flooding for eor2020Ingår i: Nanomaterials, E-ISSN 2079-4991, Vol. 10, nr 7, artikel-id 1296Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cellulose nanocrystals (CNCs) and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)- oxidized cellulose nanofibrils (T-CNFs) were tested as enhanced oil recovery (EOR) agents through core floods and microfluidic experiments. Both particles were mixed with low salinity water (LSW). The core floods were grouped into three parts based on the research objectives. In Part 1, secondary core flood using CNCs was compared to regular water flooding at fixed conditions, by reusing the same core plug to maintain the same pore structure. CNCs produced 5.8% of original oil in place (OOIP) more oil than LSW. For Part 2, the effect of injection scheme, temperature, and rock wettability was investigated using CNCs. The same trend was observed for the secondary floods, with CNCs performing better than their parallel experiment using LSW. Furthermore, the particles seemed to perform better under mixed-wet conditions. Additional oil (2.9–15.7% of OOIP) was produced when CNCs were injected as a tertiary EOR agent, with more incremental oil produced at high temperature. In the final part, the effect of particle type was studied. T-CNFs produced significantly more oil compared to CNCs. However, the injection of T-CNF particles resulted in a steep increase in pressure, which never stabilized. Furthermore, a filter cake was observed at the core face after the experiment was completed. Microfluidic experiments showed that both T-CNF and CNC nanofluids led to a better sweep efficiency compared to low salinity water flooding. T- CNF particles showed the ability to enhance the oil recovery by breaking up events and reducing the trapping efficiency of the porous medium. A higher flow rate resulted in lower oil recovery factors and higher remaining oil connectivity. Contact angle and interfacial tension measurements were conducted to understand the oil recovery mechanisms. CNCs altered the interfacial tension the most, while T-CNFs had the largest effect on the contact angle. However, the changes were not significant enough for them to be considered primary EOR mechanisms.

  • 23.
    Aaen, Ragnhild
    et al.
    NTNU Norwegian University of Science and Technology, Norway.
    Lehtonen, Mari
    University of Helsinki, Finland.
    Mikkonen, Kirsi
    University of Helsinki, Finland.
    Syverud, Kristin
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Material- och ytdesign. NTNU Norwegian University of Science and Technology, Norway.
    Combining cellulose nanofibrils and galactoglucomannans for enhanced stabilization of future food emulsions2021Ingår i: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 28, nr 16, s. 10485-10500Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The use of wood-derived cellulose nanofibrils (CNFs) or galactoglucomannans (GGM) for emulsion stabilization may be a way to obtain new environmentally friendly emulsifiers. Both have previously been shown to act as emulsifiers, offering physical, and in the case of GGM, oxidative stability to the emulsions. Oil-in-water emulsions were prepared using highly charged (1352 ± 5 µmol/g) CNFs prepared by TEMPO-mediated oxidation, or a coarser commercial CNF, less charged (≈ 70 µmol/g) quality (Exilva forte), and the physical emulsion stability was evaluated by use of droplet size distributions, micrographs and visual appearance. The highly charged, finely fibrillated CNFs stabilized the emulsions more effectively than the coarser, lower charged CNFs, probably due to higher electrostatic repulsions between the fibrils, and a higher surface coverage of the oil droplets due to thinner fibrils. At a constant CNF/oil ratio, the lowest CNF and oil concentration of 0.01 wt % CNFs and 5 wt % oil gave the most stable emulsion, with good stability toward coalescence, but not towards creaming. GGM (0.5 or 1.0 wt %) stabilized emulsions (5 wt % oil) showed no creaming behavior, but a clear bimodal distribution with some destabilization over the storage time of 1 month. Combinations of CNFs and GGM for stabilization of emulsions with 5 wt % oil, provided good stability towards creaming and a slower emulsion destabilization than for GGM alone. GGM could also improve the stability towards oxidation by delaying the initiation of lipid oxidation. Use of CNFs and combinations of GGM and CNFs can thus be away to obtain stable emulsions, such as mayonnaise and beverage emulsions. © 2021, The Author(s).

  • 24.
    Aagaard Fransson, Erik Johannes
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Elektroteknisk teori och konstruktion.
    Wall-Horgen, Tobias
    KTH, Skolan för elektro- och systemteknik (EES), Elektroteknisk teori och konstruktion.
    Building and Evaluating a 3D Scanning System for Measurementsand Estimation of Antennas and Propagation Channels2012Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Wireless communications rely, among other things, on theunderstanding of the properties of the radio propagationchannel, the antennas and their interplay. Adequate measurementsare required to verify theoretical models and togain knowledge of the channel behavior and antenna performance.As a result of this master thesis we built a 3D fieldscanner measurement system to predict multipath propagationand to measure antenna characteristics. The 3Dscanner allows measuring a signal at the point of interestalong a line, on a surface or within a volume in space. In orderto evaluate the system, we have performed narrowbandchannel sounding measurements of the spatial distributionof waves impinging at an imaginary spherical sector. Datawas used to estimate the Angle-of-Arrivals (AoA) and amplitudeof the waves. An estimation method is presented tosolve the resulting inverse problem by means of regularizationwith truncated singular value decomposition. The regularizedsolution was then further improved with the helpof a successive interference cancellation algorithm. Beforeapplying the method to measurement data, it was testedon synthetic data to evaluate its performance as a functionof the noise level and the number of impinging waves. Inorder to minimize estimation errors it was also required tofind the phase center of the horn antenna used in the channelmeasurements. The task was accomplished by directmeasurements and by the regularization method, both resultsbeing in good agreement.

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  • 25.
    Aagaard, Sebastian
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Demonstrating customer and business value through the implementation of a Design for Reliability Program2023Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Inom industrin är det allmänt vedertaget att genomförandet av ett program för Design for Reliability (DfR) kan minska garantikostnaderna, öka kundvärdet och minska totalkostnaden för ägande (TCO) när det tillämpas inom både produktutveckling och produktförbättringsprojekt. DfR är en uppsättning verktyg och relaterade produktutvecklingsprocesser för att förbättra en produkts tillförlitlighet över tiden genom förändringar i produktkonstruktionen och tillverkningsprocessen. Denna forskningsverksamhet syftade till att visa kund- och affärsvärdet av att genomföra ett DfR-program vid Epiroc Surface Division. Detta undersöktes ur perspektivet av utvalda projekt och produktutvecklingsaktiviteter med fokus på Epiroc SmartROC D65 borrigg, som aktivt har arbetat med tillförlitlighetsverktygen.I studien drogs slutsatsen att genomförandet av DfR-programmet har gett ett påtagligt affärsvärde. Det förbättrade verktyget Early-Life Reliability gör det nu möjligt att bättre utvärdera affärsvärdet. Detta värde har främst härletts från möjligheten att analysera minskade garantikostnader och förbättringar av den genomsnittliga tiden mellan händelser (MTBE), en delmängd av den genomsnittliga tiden mellan fel (MTBF). En metod har utvecklats för att fastställa affärsvärdet i form av kostnadsbesparingar. Ur ett kundperspektiv, när TCO betraktas, kan det visas att ett aktivt arbete med tillförlitlighetsverktygen under produktutvecklingen har en positiv inverkan på utrustningens mekaniska tillgänglighet och produktivitet, vilket leder till förbättringar av TCO. De viktigaste verktygen som används i studien är det förbättrade verktyget Early-Life Reliability och riskhanteringsverktyg som används under produktutvecklingen för att tidigt identifiera potentiella felsteg.I studien drogs slutsatsen att de viktigaste möjligheterna att förbättra DfR-programmet är att öka insamlingen av relevanta data under utrustningens hela livslängd och inte bara under den tidiga livslängden under garantiperioden. Dessutom skulle det vara önskvärt att registrera och rapportera faktiska MTBF-data för att få ett bredare perspektiv än vad MTBE för närvarande ger. En förbättring av kvaliteten och tillförlitligheten hos de indata som används i verktyg som rapporten Early-Life Reliability skulle avsevärt förbättra resultatet av denna tillgång. Det har visats att data kan användas effektivt. Den förbättrade versionen av verktyget är inte tillgänglig för utbredd användning inom organisationen. Men när den väl släpps kan den vara en stor möjlighet att förbättra DfR i samband med den utvecklade metoden för att prioritera insatser och påvisa kund- och affärsvärde.

  • 26.
    Aagah, Orod
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Aryannejad, Siavash
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Bro- och stålbyggnad.
    Dynamic analysis of soil-steel composite railway bridges: FE-modeling in Plaxis2014Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    A soil-steel composite bridge is a structure comprised of corrugated steel plates, which are joined with bolted connections, enclosed in friction soil material on both sides and on the top. The surrounding friction soil material, or backfill, is applied in sequential steps, each step involving compaction of the soil, which is a necessity for the construction to accumulate the required bearing capacity. Soil-steel composite bridges are an attractive option as compared with other more customary bridge types, owing to the lower construction time and building cost involved. This is particularly true in cases where gaps in the form of minor watercourses, roads or railways must be bridged.

    The objective of this master thesis is the modelling of an existing soil-steel composite railway bridge in Märsta, Sweden with the finite element software Plaxis. A 3D model is created and calibrated for crown deflection against measurement data collected by the Division of Structural Engineering and Bridges of the Royal Institute of Technology (KTH) in Stockholm, Sweden.

    Once the 3D model is calibrated for deflection, two 2D models with different properties are created in much the same way. In model 1, the full axle load is used and the soil stiffness varied, and in model 2 the soil stiffness acquired in the 3D model is used and the external load varied. The results are compared to measurement data. In 2D model 1 an efficient width of 1,46 m for the soil stiffness is used in combination with the full axle load, and in 2D model 2 an efficient width of 2,85 m is used for the external load, in combination with the soil stiffness acquired in the 3D model.

    Aside from this, parametric studies are performed in order to analyse the effect of certain input parameters upon output results, and in order to analyse influence line lengths.

    Recreating the accelerations and stresses in the existing bridge using finite element models is complicated, and the results reflect this. Below are shown the discrepancies between model results and measurement data for the pipe crown. The scatter in the measurement data has not been taken into consideration for this; these specific numbers are valid only for one particular train passage.

    For crown deflection, the 3D model shows a discrepancy of 4%, 2D model 1 5% and 2D model 2 8% compared with measurement data. For crown acceleration, in the same order, the discrepancy with measurements is 1%, 71% and 21% for maximum acceleration, and 46%, 35% and 28% for minimum acceleration. For maximum crown tensile stress, the discrepancy is 95%, 263% and 13%. For maximum crown compressive stress, the discrepancy is 70%, 16% and 46%.

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  • 27.
    Aagah, Orod
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap.
    Kardan, Caesar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap.
    Ett tillgängligt och användarvänligt boende: Anpassningsmöjligheter för människor med rörelsehinder och nedsatt rörelseförmåga2012Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In this paper we have theoretically built a house designed for people with impaired mobility. The

    essay begins with an introduction in which the purpose of the work, the methodology and the

    depth-research part is presented. Then the layout that explains how we intend to adapt the house

    for the demands detailed in the depth-research part is presented. In the same chapter various

    structural components, such as different floors and walls, are specified.

    In the selection of materials we have taken into account the criteria of our specialization and

    adaptation to the aesthetic aspects, where we evaluate materials based upon our wishes regarding

    technique and form. There are also other aspects that are important in the selection of materials,

    including that these are adapted to technical traits of the construction elements and installations.

    In a later chapter the technical installations such as ventilation systems, heating systems,

    electricity and sanitation are presented, where both technical and financial aspects are described

    in detail. The economic aspects are also described in connection with calculating the building's

    power and energy requirements and then presented in the section where costs are accounted for.

    Finally, the work is summarized in the section “Conclusion and Discussion” in which we analyze

    all the work, and based on these analyses conclusions are drawn. During the course of work

    regulations such as Boverkets Byggregler (BBR) and other sources were used. These sources are

    presented in the bibliography section. We also received help and guidance from our supervisors

    in various parts of the work, which we are grateful for.

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  • 28.
    Aagerup, Ulf
    et al.
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, Centrum för innovations-, entreprenörskaps- och lärandeforskning (CIEL).
    Frank, Anna-Sofia
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Hultqvist, Evelina
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    The persuasive effects of emotional green packaging claims2019Ingår i: British Food Journal, ISSN 0007-070X, E-ISSN 1758-4108, Vol. 121, nr 12, s. 3233-3246Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose - The purpose of this paper is to investigate the effects of rational green packaging claims vs emotional green packaging claims on consumers' purchase propensity for organic coffee.

    Design/methodology/approach - Three within-subjects experiment were carried out (N=87, N=245, N=60). The experimental design encompasses packaging with rational green claims, emotional green claims, as well as a neutral (control) claim. Measured variables are introduced to assess participants' environmental commitment and information processing ability. A manipulated between-subjects variable is introduced to test how distraction interacts with preference for the claims.

    Findings - Overall, consumers prefer products with green claims over those with neutral (control) claims, and products with emotional green claims to those with rational green claims. The studies also reveal that this effect is moderated by participants' environmental commitment, information processing ability and by distraction. The findings were statistically significant (p<0.05).

    Research limitations/implications - As a lab experiment, the study provides limited generalizability and external validity. Practical implications - For most organic FMCG products, it is advisable to employ emotional packaging claims.

    Social implications - The presented findings provide marketers with tools to influence consumer behavior toward sustainable choices.

    Originality/value - The paper validates previous contributions on the effects of product claim types, and extends them by introducing comprehensive empirical data on all the Elaboration Likelihood Model's criteria for rational decision-making; motivation, opportunity and ability.

  • 29.
    Aagerup, Ulf
    et al.
    Högskolan i Halmstad, Centrum för innovations-, entreprenörskaps- och lärandeforskning (CIEL).
    Frank, Anna-Sofia
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    Hultqvist, Evelina
    Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap.
    The persuasive effects of emotional green packaging claims2019Ingår i: British Food Journal, ISSN 0007-070X, E-ISSN 1758-4108, Vol. 121, nr 12, s. 3233-3246Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Purpose - The purpose of this paper is to investigate the effects of rational green packaging claims vs emotional green packaging claims on consumers' purchase propensity for organic coffee.

    Design/methodology/approach - Three within-subjects experiment were carried out (N=87, N=245, N=60). The experimental design encompasses packaging with rational green claims, emotional green claims, as well as a neutral (control) claim. Measured variables are introduced to assess participants' environmental commitment and information processing ability. A manipulated between-subjects variable is introduced to test how distraction interacts with preference for the claims.

    Findings - Overall, consumers prefer products with green claims over those with neutral (control) claims, and products with emotional green claims to those with rational green claims. The studies also reveal that this effect is moderated by participants' environmental commitment, information processing ability and by distraction. The findings were statistically significant (p<0.05).

    Research limitations/implications - As a lab experiment, the study provides limited generalizability and external validity. Practical implications - For most organic FMCG products, it is advisable to employ emotional packaging claims.

    Social implications - The presented findings provide marketers with tools to influence consumer behavior toward sustainable choices.

    Originality/value - The paper validates previous contributions on the effects of product claim types, and extends them by introducing comprehensive empirical data on all the Elaboration Likelihood Model's criteria for rational decision-making; motivation, opportunity and ability.

  • 30. Aagesen, Peter Tolstrup
    et al.
    Heyer, Clint
    Malmö högskola, Fakulteten för kultur och samhälle (KS), Institutionen för konst, kultur och kommunikation (K3).
    Personality of Interaction: Expressing Brand Personalities Through Interaction Aesthetics2015Ingår i: 34th annual Chi Conference On Human Factors in Computing Systems, Chi 2016, ACM Digital Library, 2015, s. 3126-3130Konferensbidrag (Refereegranskat)
    Abstract [en]

    Practicing designers must usually relate to branding in some manner. A designed artifact must support the brand in a constructive way and help establish positive brand experiences, which in turn have strategic value for the brand's institution. While there is obvious application of visual branding knowledge to the visual form of interactive artifacts, interviews with expert practitioners reveal a lack of systematic means to craft an interaction aesthetic to support a brand. Our empirical study relates attributes of interactive experience to that of 'brand personality', a common way of quantifying how a brand should be perceived. We show that particular attributes of interactivity, such as whether an interaction has a continuous rather than discrete flow, are related to particular brand traits. Our empirical results establish a clear commercial significance for deeper, systematic ways of analyzing and critiquing interactive experiences.

  • 31.
    Aakash, förnamn
    et al.
    Department of Electronics and Communication Engg., Birla Institute of Technology.
    Nordblad, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Mohan, Rajendra
    Department of Physics, National Institute of Technology Patna.
    Mukherjee, Samrat
    Department of Physics, National Institute of Technology Patna.
    Structural, magnetic and hyperfine characterizations of nanocrystalline Zn-Cd doped nickel ferrites2017Ingår i: Journal of Magnetism and Magnetic Materials, ISSN 0304-8853, E-ISSN 1873-4766, Vol. 441, s. 710-717Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In our present work, we have synthesized a series of Cd-Zn doped nickel ferrite ((Cd-0.5 Zn-x(x)) Ni0(.5)Fe(2)O(4); x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5) through standard chemical co-precipitation method to study the influence of diamagnetic ions (Cd, Zn) on the magnetic properties of ferrites. XRD and Raman spectroscopy were employed for the structural characterizations. The refinement of the X-ray diffractogram data augmented by the Williamson-Hall plots showed the presence of Cd2+ vacancies and a strained crystal structure. The vibrational spectroscopy indicated the presence of lower space-group symmetry and a distorted crystal structure. Magnetic measurements showed the samples possessed low magnetic anisotropy along with a canted spin structure. The Mossbauer measurements confirmed the cation distribution and gave evidence of super transferred hyperfine interactions arising due to canted spin structure of the system.

  • 32.
    aala, elsafei
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för byggnadsteknik, energisystem och miljövetenskap.
    Numerical study of flow development in the near and intermediate field of a free round jet2020Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
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  • 33.
    Aalberg, L
    et al.
    National Bureau of Investigation, Finland.
    Andersson, K
    Swedish National Laboratory of Forensic Science.
    Bertler, C
    Swedish National Laboratory of Forensic Science.
    Cole, MD
    University of Strathclyde, Glasgow.
    Finnon, Y
    University of Strathclyde, Glasgow.
    Huizer, H
    Netherlands Forensic Institute.
    Jalava, K
    National Bureau of Investigation, Finland.
    Kaa, E
    Aarhus Universitet.
    Lock, E
    Université de Lausanne.
    Lopes, A
    Laboratorio Policia Cientifica, Lisbon, Portugal.
    Poortman-van der Maar, A
    Netherlands Forensic Institute.
    Sippola, E
    National Bureau of Investigation, Finland.
    Dahlén, Johan
    Swedish National Laboratory of Forensic Science.
    Development of a harmonised method for the profiling of amphetamines: II. Stability of impurities in organic solvents2005Ingår i: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 149, nr 03-Feb, s. 231-241Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The present study focused on the stability of 22 amphetamine impurities dissolved in six organic solvents: isooctane, toluene, ethanol, dichloromethane, ethyl acetate, and diethyl ether. The aim was to find the most inert, and thereby most suitable, solvent for amphetamine profiling. Mixtures of the impurities were prepared in the different solvents, and changes in the concentrations of the individual compounds over-time were monitored by gas chromatographic analysis after 0, 4, 12, 24, 48, and 96 h. Isooctane and toluene provided the most inert conditions, although, a few of the impurities were insufficiently stable in these two solvents. The present experiments were performed as a part of the development of a harmonised method for profiling of amphetamine. The results can be used to support the choice of organic solvents for sample preparation. They also provide information about the stability of the impurities that are found in profiles of illicit amphetamine. This is essential due to the fact, that unstable compounds can have a negative influence on the comparison of profiles.

  • 34. Aalhuizen, Christoffer
    Potential of V2G in a Rural Low-Voltage Grid on Gotland for Voltage and Power Capacity Control2019Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The Swedish transportation sector needs to undergo major changes in order to achieve the established goals for climate and environment. The largest change is the replacement of fossil-fuelled vehicles to vehicles propelled by renewable energy sources, such as biofuels and electricity. To account for an increase in local electric power consumption, the electric power infrastructure of Sweden needs to adapt through expansion and reconstruction of the electric power grid. However, changes in infrastructure are usually expensive. It is therefore suitable to also examine alternative solutions, which could potentially be more cost efficient. One of these solutions are vehicle-to-grid (V2G), where electric vehicles acts as local electric power control and provides auxiliary services to the electric power grid. This thesis is a case study of a part of a low-voltage electric power grid on Gotland, with the goal of analysing the potential of V2G in the investigated area. The study focused on utilizing V2G for balancing electric power consumption and generation, and for adjusting voltage levels. Simulations of the area were executed in PSS®E for three different cases; one high-load case, low-load case and average-load case. It was found that by utilizing V2G a ramp up of electric power during mornings was delayed by approximately one hour, making the electric power grid potentially more compatible with photovoltaics (PV). However, the overall effects from V2G was fairly low. This outcome can partly be explained by the assumptions made in the report, and also due to some odd behaviour of the system model. 

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  • 35.
    Aalipour, Mojgan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Human Factors Approach for Maintenance Improvement2015Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The purpose of this research work is to explore and describe human factors affectingmaintenance execution. To achieve the purpose of this study, the influencing factors have been identified using a literature survey. They have been categorized into four main groups namely organizational, workplace, job and individual factors. The Analytical Hierarchy Process (AHP) method is employed on data questionnaires to rank the priority of the factors. The interrelationships between these factors have been recognized by theInterpretive Structural Modelling (ISM) model. In the present case studies, MICMAC1analysis technique is also implemented for identifying the driving, dependent, linkage and autonomous factors. The data was collected through a questionnaire survey involving the participation of 16 and 25 maintenance staff and 10 mining experts in Swedish and Iranian mines, respectively. Within the study, it has been identified that the temperature, work layout, tools design and tools availability are the most important factors in both mines related to these categories. However, the significant factors in the organizational and individual categories are different in the selected mines. The effect of workplace factors on the maintainability of mining equipment is discussed and thereafter a methodology for maintainability management in the design and operation phases is developed. In the thirdcase study HEART2 is applied to estimate the probability of human error occurring duringmaintenance execution in an Iranian cable company. This research supports maintenance management to gain knowledge of human factors that affect maintenance execution. Further, this understanding could be useful in the development of strategies to improve the execution of maintenance.Keywords: Human Factors, Maintenance Management, Human Reliability, HumanPerformance, AHP, ISM, MICMAC, HEART

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  • 36.
    Aalipour, Mojgan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Ayele, Yonas Zewdu
    Department of Engineering and Safety, UiT The Arctic University of Norway, Tromsø.
    Barabadi, Abbas
    Tromsø University, Department of Engineering and Safety, UiT The Arctic University of Norway, Tromsø.
    Human reliability assessment (HRA) in maintenance of production process: a case study2016Ingår i: International Journal of Systems Assurance Engineering and Management, ISSN 0975-6809, E-ISSN 0976-4348, Vol. 7, nr 2, s. 229-238Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Human reliability makes a considerable contribution to the maintenance performance, safety, and cost-efficiency of any production process. To improve human reliability, the causes of human errors should be identified and the probability of human errors should be quantified. Analysis of human error is very case-specific; the context of the field should be taken into account. The aim of this study is to identify the causes of human errors and improve human reliability in maintenance activities in the cable manufacturing industry. The central thrust of this paper is to employ the three most common HRA techniques—human error assessment and reduction technique, standardized plant analysis risk-human reliability, and Bayesian network—for estimating human error probabilities and then to check the consistency of the results obtained. The case study results demonstrated that the main causes of human error during maintenance activities are time pressure, lack of experience, and poor procedure. Moreover, the probabilities of human error, obtained by employing the three techniques, are similar and consistent

  • 37.
    Aalipour, Mojgan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Barabadi, Abbas
    Tromsø University, University of Tromsø - The Arctic University of Norway.
    Work place factors effect on maintainability in challenging operating conditions2015Ingår i: 2015 IEEE International Conference on Industrial Engineering and Engineering Management (IEEM): Singapore, 6-9 Dec. 2015, Piscataway, NJ: IEEE Communications Society, 2015, s. 767-771, artikel-id 7385751Konferensbidrag (Refereegranskat)
    Abstract [en]

    Some industries such as mining industry create complex and challenging work place for maintenance crews. For example in an underground mine, for some machines, heavy maintenance tasks must be performed on site in a limited workspace in a harsh environment, including dust and improper illumination. Such operating conditions can increase the health, safety, and environment (HSE) risk, reduce the availability of the machines and increase the life cycle cost of equipment. A review of current mining equipment design and maintenance procedure confirms that considerable reduction in HSE risk, as well as substantial cost savings, can be achieved by considering human factors. This study discusses the effect of workplace factors on the maintainability of mining equipment. It presents the results from questionnaires on the effect of work place factors on maintainability performance given to maintenance staff at two mines, one in northern Sweden and the other in Iran.

  • 38.
    Aalipour, Mojgan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Singh, Sarbjeet
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Identification of Factors affecting Human performance in Mining Maintenance tasks2014Ingår i: Proceedings of the 3rd international workshop and congress on eMaintenance: June 17-18 Luleå, Sweden : eMaintenance, Trends in technologies & methodologies, challenges, possibilites and applications / [ed] Uday Kumar; Ramin Karim; Aditya Parida; Philip Tretten, Luleå: Luleå tekniska universitet, 2014, s. 71-76Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper investigates the factors affecting humanperformance in maintenance task in mining sector. Theobjective is identify various factors and to classify them asdriving (strong driving power and weak dependence) anddependent factors (weak driving power and strongdependence). The factors were identified through literaturesurvey and are ranked using mean score of data questionnaire.The reliability of measures is pretested by applyingCronbach’s alpha coefficient to responses to a questionnairegiven to maintenance personnel. The interrelationshipsbetween human factors have been recognized by interpretivestructural modeling (ISM). Further, these factors have beenclassified using matrice d'impacts croises-multiplicationappliqué à un classement (MICMAC) analysing. This casestudy will figure out the factors affecting human performancefor deriving maintenance management insights to improveproductivity in the mining sector. Further, this understandingmay be helpful in framing the policies and strategies formining industry. Temperature, lighting, documentation,communication and fitness are driving factors. Moreover,Work layout, tools availability, complex tasks, time pressure,safety, boss decisions, training, fatigue and motivation havestrong driving power as well as high dependencies and itcomes under the category of linkage factors.

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  • 39.
    Aaltio, Iiris
    et al.
    School of Economics and Business University of Jyväskylä, Finland.
    Kyrö, PaulaHelsinki School of Economics, Finland.Sundin, ElisabethLinköpings universitet, Institutionen för ekonomisk och industriell utveckling, Företagsekonomi. Linköpings universitet, Filosofiska fakulteten.
    Women, Entrepreneurship and Social Capital: A Dialogue and Construction2008Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
    Abstract [en]

    This book explores social capital as the multiple relationships between gender, management and entrepreneurship. Human resources are the social capital of a firm and business life, based on trust as well as on expertise, values and cultural diversity. This calls for cross-cultural knowledge and an understanding of gender issues and individual differences in the social capital of the firm and society. The dialogue between women entrepreneurship and social capital theory and research has its special place among other women entrepreneurship books, the number of which has lately increased. It strengthens still in some respect the fragmented voice of women entrepreneurship research by providing a landscape of women entrepreneurs as creators of, and created by, social capital. It indicates how women entrepreneurs appear to have a special position in forming, developing and reorganizing the social capital in the business world. In its eleven chapters, twenty-six researchers representing a variety of disciplines from different parts of the world are presenting findings on diverse aspects of the dialogue between women entrepreneurship and social capital. As a consequence the central concepts, social capital, entrepreneurship and gender, are given a variety of meanings. Women entrepreneurs and business owners regardless of their cultural context, branch and education provide interesting ideas to the global debate on equality and social capital.

  • 40.
    Aalto, Jonatan
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Betongbyggnad.
    Neuman, Elisabeth
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Betongbyggnad.
    Comparison of Punching Shear Design Provisions for Flat Slabs2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Abstract

    A new generation of EN 1992-1-1 (2004) also known as Eurocode 2 is under development

    and currently there is a set of proposed provisions regarding section 6.4

    about punching shear, PT1prEN 1992-1-1(2017). It was of interest to compare the

    proposal with the current punching shear design provisions.

    The aim of this master thesis was to compare the punching shear resistance obtained

    in accordance with both design codes. Furthermore the eect of some parameters

    on the resistance was to be compared. It was also of interest to evaluate the userfriendliness

    of the proposal.

    In order to meet the aim, a case study of a real  at slab with drop panels was performed

    together with a parametric study of a pure ctive  at slab. The parametric

    study was performed for inner, edge and corner columns in the cases prestressed,

    without and with shear reinforcement.

    It was concluded that the distance

    av from the column axis to the contra  exural

    location has a big in uence on the punching shear resistance. The factor

    ddg

    considering concrete type and aggregate properties also has a big impact on the resistance.

    The simplied estimation of

    av according to 6.4.3(2) in PT1prEN 1992-1-1

    (2017) may be inaccurate in some cases.

    The length

    b0 of the control perimeter has a larger eect on the resistance in EN

    1992-1-1 (2004) than in PT1prEN 1992-1-1 (2017).

    In PT1prEN 1992-1-1 (2017), studs located outside the second row has no impact

    on the resistance.

    The tensioning force in a prestressed  at slab has a larger in uence on the resistance

    in PT1prEN 1992-1-1 (2017) than in EN 1992-1-1 (2004). Furthermore,

    the reinforcement ratio is increased by the tendons, and thus aect the resistance in

    PT1prEN 1992-1-1 (2017).

    Clearer provisions for the denition of the support strip

    bs for corners and ends

    of walls are needed in PT1prEN 1992-1-1 (2017).

    It may be questionable if the reduction of the perimeter for a large supported area in

    accordance with 6.4.2(4) in PT1prEN 1992-1-1 (2017) underestimates the resistance

    v

    in some cases.

    Considering the work-load with PT1prEN 1992-1-1 (2017), more parameters are

    included. However, they may not require that much eort to obtain.

    Keywords: Punching shear, resistance, concrete,  at slab, design provisions, Eurocode

    2, case study, parametric study, shear reinforcement, prestressed

    vi

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  • 41.
    Aaltonen, Harri
    et al.
    Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland.
    Sierla, Seppo
    Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland.
    Subramanya, Rakshith
    Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland.
    Vyatkin, Valeriy
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap. Department of Electrical Engineering and Automation, School of Electrical Engineering, Aalto University, FI-00076 Espoo, Finland; International Research Laboratory of Computer Technologies, ITMO University, 197101 St. Petersburg, Russia.
    A simulation environment for training a reinforcement learning agent trading a battery storage2021Ingår i: Energies, E-ISSN 1996-1073, Vol. 14, nr 17, artikel-id 5587Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Battery storages are an essential element of the emerging smart grid. Compared to other distributed intelligent energy resources, batteries have the advantage of being able to rapidly react to events such as renewable generation fluctuations or grid disturbances. There is a lack of research on ways to profitably exploit this ability. Any solution needs to consider rapid electrical phenomena as well as the much slower dynamics of relevant electricity markets. Reinforcement learning is a branch of artificial intelligence that has shown promise in optimizing complex problems involving uncertainty. This article applies reinforcement learning to the problem of trading batteries. The problem involves two timescales, both of which are important for profitability. Firstly, trading the battery capacity must occur on the timescale of the chosen electricity markets. Secondly, the real-time operation of the battery must ensure that no financial penalties are incurred from failing to meet the technical specification. The trading-related decisions must be done under uncertainties, such as unknown future market prices and unpredictable power grid disturbances. In this article, a simulation model of a battery system is proposed as the environment to train a reinforcement learning agent to make such decisions. The system is demonstrated with an application of the battery to Finnish primary frequency reserve markets.

  • 42.
    Aaman, Sophia
    et al.
    KTH, Skolan för industriell teknik och management (ITM).
    Hessel Lundberg, Johan Henrik
    KTH, Skolan för industriell teknik och management (ITM).
    Setting the seeds for a green growth -A Study of biofuel development in Indonesia’s transport sector2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Climate change poses as one of the major environmental issues on a global scale today, with one of the largest contributor to the climate change being the greenhouse gas (GHG) emissions. GHG emissions in turn is known to a large extent originate in anthropogenic energy use, especially fossil fuel usage. This leads to almost a quarter of the global emissions today being emitted from the transport sector as the sector is primary fueled by fossil fuels.

    Biofuels have been promoted as a strong candidate for fossil fuel substitution as it has similar properties while being renewable. However, even as biofuels have been increasing annually since 2008 globally, there are still concerns associated with the usages that have hindered its replacement of fossil fuels.

    Indonesia, one of the most populated countries in Southeast Asia, is projected to be one of the world’s leading economies in 2050. In 2030, Indonesia in projected to have doubled its energy consumption since 2014, indicating that the decisions and actions taken today in Indonesia will have a significant impact on the future fuel consumption. This, in combination with being the largest producer of palm oil in the world, gives it a great potential to be in a leading position in the future production of biofuels, especially biodiesel from palm oil. Additionally, Indonesia has set mandatory targets for biofuel share in the transport sector which indicates that the country also seeks to promote the usages of biofuels.

    This thesis intends to investigate Indonesia’s potential for biofuel development in the transport sector and which factors that could hinder it. More specifically, this study answers the two questions: (i) Which factors are hampering the development of biofuels in the Indonesian transportation sector from a multi-level perspective? and (ii) What is the projection of the Indonesian transport sector by 2030 in terms of fuel consumption and global warming potential (GWP) and what role could biofuels play in reducing those?

    The data used were collected by interviews with stakeholders in Indonesia and a literature study, which afterwards was processed with the tools Multi-Level Perspective (MLP) and Long-range Energy Alternatives Planning (LEAP). MLP is a concept aiming to describe how system transitions happens with the help of an examination of the linkages in between technology and society, whereas LEAP is an energy modeling tool used in order to create energy projections in different policy scenario options. In this research, MLP were used to capture and analyze the factors that influence the future implementation of biofuels in Indonesia from a socio-technical perspective, putting forward key barriers for biofuel implementation in Indonesia. LEAP was used to construct a model of the Indonesian transport sector to project the future fuel consumption and GWP emissions. This was used to examine biofuels importance as a fuel through scenarios where different Indonesian policy actions were appraised. Together, these two methods will provide an enlightening and concluding remark on the future possibilities for biofuels in Indonesia's transport sector in this thesis.

    The major finding of the first research question were that biofuels in Indonesia were being introduced in Indonesia as the government saw economic benefits and a solution to the increased energy demand in Indonesia and an increased energy security in going towards a domestic produced energy source. The need for biofuels were also increased due to an increased global sustainability awareness, which also reached Indonesia.

    Today, biofuels in Indonesia is in a socio-technical transition pathway to go from a niche innovation to a technology in the regime level, but in order for a breakthrough, a number of barriers needs to be addressed. The most mentioned barriers were the institutional and regulatory barriers, which mainly lays in a lack of cooperation amongst the regulatory institutions and a low rate of success of biofuel laws and regulations. Other barriers were the market barriers, closely connected in a subsidization of fossil fuels in Indonesia and a need for further subsidization of biofuels for the market for biofuels to exist in Indonesia. Furthermore, a technical barrier with the vehicle engine were seen as the engine needs improvements in order for a higher blending of biofuels in the fuel. There was also a concern of the perceived sustainability of biofuels in general (e.g. water scarcity and pollution) which was identified as a hindrance. It was also clear a social change is needed in order to push the biofuel breakthrough and enable it to reach its full potential. Today, the interviewees mainly see a development for the biofuel biodiesel and not for the biofuel bioethanol in Indonesia, which they mainly concluded as there is currently none or very little production and demand for bioethanol in Indonesia, and as well a lack of governmental support for bioethanol development.

    For the second research question four scenarios were used; Business as Usual (a continuation of current trends), Improved Standards (an investigation of higher emissions standards and an increasing fuel efficiency), Biofuel Mandate (a mandatory biofuel share in fuels) and the Low Carbon scenario (a combination of the previous two as well as introduction of electric vehicles, changed car preferences and higher biofuel blending targets). Cars represents a tenth of the vehicle fleet and the share of diesel car amongst the cars are 5% while gasoline stands for 95%, the rest of the vehicles are gasoline driven motorcycles. The main findings were: the total vehicle fleet will have doubled by 2030. This rapid increase could cause stress on the domestic fuel supply, as the yearly fuel consumption is expected to grow from 770 million GJ in 2014 to 1850 million GJ in 2030, an increase by 140%. In the projection the fossil fuels are blended with biofuels, diesel is mixed with biodiesel while gasoline is blended with bioethanol. The annual diesel fuel consumption is projected to increase from 350 million liters to 1100 million in the Business as Usual scenario where the current trend was expected to continue. The implementation of biodiesel and bioethanol in the Biofuel Mandate scenario. Additionally, the Biofuel Mandate scenario resulted in a 12.6% reduction of GHG emissions during the projected period. The cumulative GHG emissions in the projection is estimated to be 1630 million tonnes of carbon dioxide equivalents in 2030 for the Business as Usual scenario. In the transport sector, gasoline is projected to increase from 23 billion liters to 54 billion liters over the period. In the Improved Standards scenario, where the emission standards are increased from Euro2 to Euro6 in 2030 for cars and Euro4 for motorcycles in 2025 as well as an annual fuel economy improvement of 2%, the total fuel consumption is reduced with 20% and GWP by 18%. It was found that the annual GWP could be reduced by almost 31% below the 2014 level, at 47 million metric tonnes of CO2Eq, if the actions of the Low Carbon scenario were achieved.

    The barriers associated with the Improved Standards scenario were technical, institutional and regulatory while the Biofuel Mandate scenario also had financial, market and distribution barriers. The Low Carbon scenario had barriers from all of the identified barrier categories. The institutional and regulatory barrier was the most prevailing barrier for all of the scenarios.

    The recommended actions based on the content of this thesis is to firstly promote collaboration between governmental institutes, stakeholders and authorities and include all stakeholders in the decision progress, this way, frameworks and regulations will have a chance to improve and increase the knowledge about biofuels in all levels. It is also important to implement a stronger biofuel R&D culture, promote a more sustainable biofuel development and increase the public awareness of biofuels. The implementation of biofuels will have a reducing effect on the total GWP and fossil fuel consumption. Gasoline is projected to remain the predominant fuel in the transport sector. Therefore will actions targeting the reduction or substitution of gasoline be more impactful than those towards diesel. However due to the availability and current production capacity of biodiesel there is still potential for higher share of biodiesel in fuels.

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  • 43.
    Aamir Latif, Muhammad
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Radar scattering from bodies of revolution using an efficient partial differential equation algorithm2008Självständigt arbete på avancerad nivå (magisterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    A technique is presented for solving the problem of scattering by a three-dimensional body of revolution using a partial differential equation (PDE) technique, employed in conjunction with radiation boundary condition applied in the Fresnel region of the scatterer. The radiation boundary condition, which is used to truncate the PDE mesh, is based upon an asymptotic expansion derived by Wilcox. Numerical results illustrating the procedure and verifying the accuracy of the results are included. These results are compared with other theoretical calculations for perfectly conducting bodies of revolution of arbitrary shape.

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  • 44.
    Aamir, Muhammad Haseeb
    et al.
    Ecole Nationale Supérieure de Géologie, GeoRessources, University of Lorraine, Vandoeuvre-lès-Nancy, France; University of Engineering and Technology, Lahore, Punjab, Pakistan.
    Gonçalves, Pedro Pereira
    Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Peñalolén, Santiago, Chile.
    Otsuki, Akira
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik. Ecole Nationale Supérieure de Géologie, GeoRessources, University of Lorraine, Vandoeuvre-lès-Nancy, France; Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Peñalolén, Santiago, Chile; Neutron Beam Technology Team, RIKEN Center for Advanced Photonics, RIKEN, Wako, Saitama, Japan.
    Complementary results of non-destructive elemental assay and liberation analysis of waste printed circuit boards2024Ingår i: Non-Destructive Material Characterization Methods / [ed] Otsuki, Akira; Jose, Seiko; Mohan, Manasa; Thomas, Sabu, Elsevier , 2024, s. 767-782Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 45.
    Aamir, Syed Ahmed
    Linköpings universitet. Linköpings universitet, Institutionen för systemteknik.
    A 65nm, Low Voltage, Fully Differential, SC Programmable Gain Amplifier for Video AFE2010Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Due to rapid growth of home entertainment consumer market, video technology has been continuously pushed to deliver sharper pictures with higher resolution. This has brought about stringent requirements on the video analog front end, which often coupled with the low power and low voltage regulations had to deal with short channel effects of the deep submicron CMOS processes.

    This thesis presents the design of a fully differential programmable gain amplifier, as a subcircuit of a larger video digitizing IC designed at division of Electronic Systems. The switched capacitor architecture of the PGA does not only buffer the signal, but performs compensation for the sync-tip of analog video signal.

    The pseudo differential OTA eliminates tail current source and maintains high signal swing and has efficient common mode feedforward mechanism. When coupled with a similar stage provides inherent common moode feedback without using an additional SC-CMFB block.

    The PGA has been implemented using a 65 nm digital CMOS process. Expected difficulties in a 1.2 V OTA design make themselves evident in 65 nm, which is why cascaded OTA structures were inevitable for attaining gain specification of 60 dB. Nested Miller compensation with a pole shifting source follower, stabilizes the multipole system. The final circuit attains up to 200 MHz bandwidth and maintains high output swing of 0.85 V. High slew rate and good common mode and power supply rejection are observed. Noise requirements require careful design of input differential stage. Although output source follower stabilized the system, it reduces significant bandwidth and adds to second order non-linearity.

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  • 46.
    Aamir, Syed Ahmed
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniksystem. Linköpings universitet, Tekniska högskolan.
    Wikner, J Jacob
    Linköpings universitet, Institutionen för systemteknik, Elektroniksystem. Linköpings universitet, Tekniska högskolan.
    A 1.2-V pseudo-differential OTA with common-mode feedforward in 65-nm CMOS2010Ingår i: Proceedings of the 17th IEEE International Conference on Electronics, Circuits, and Systems, Institute of Electrical and Electronics Engineers (IEEE), 2010, s. 29-32Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this work, we describe the implementation of a 1. 2-V pseudo-differential operational transconductance amplifier (OTA) with common-mode feedforward (CMFF) and inher­ent common-mode feedback (CMFB) in a 65-nm, digital CMOS process. The OTA architecture provides an inher­ent CMFB when cascaded OTA structures are utilized andthis work has studied a cascaded amplifier consisting of fourstages. Due to the low-gain using core 65-nm circuit de­vices, the overall gain must be distributed on all four stages to acquire a gain of more than 60 dB, while maintaining a-3-dB bandwidth of 200 MHz. To achieve high gain, we propose using a modified, positive-feedback, cross-coupled input differential stage. The modified OTA achieves a high output swing of ± 0.85 V due to only two stacked transistors, 88 dB DC gain and a third-order harmonic of -60 dB for 800 mVpp at 30 MHz. Further on, in a capacitive buffer configuration, we achieve a high slew rate of 1240 V/µS, -3-dB bandwidth of 509 MHz, signal-to-noise ratio of 63 dB while consuming 10.4 mW power.

  • 47.
    Aamir, Syed Ahmed
    et al.
    Linköpings universitet, Institutionen för systemteknik, Elektroniksystem. Linköpings universitet, Tekniska högskolan.
    Wikner, J Jacob
    Linköpings universitet, Institutionen för systemteknik, Elektroniksystem. Linköpings universitet, Tekniska högskolan.
    A 500-MHz low-voltage programmable gain amplifier for HD video in 65-nm CMOS2010Ingår i: Proceedings of 28th IEEE Norchip Conference., NORCHIP'10, Tampere: www.ieee.org , 2010, s. 1-4Konferensbidrag (Refereegranskat)
    Abstract [en]

    This work describes the implementation of a 1.2-V programmable gain amplifier (PGA) for high-definition (HD) video digitizers in a 65-nm digital CMOS process. The “pseudo” switched-capacitor (SC) PGA architecture buffers the video signal, without switching, during the active video. The SC circuitry is used for setup of DC operating point during horizontal and vertical blanking periods. Additionally, it compensates for the `sync-tip' of analog video signals to an equal blanking level for increased dynamic range to the digitizer following the PGA. The operational transconductance amplifier (OTA) employed as main amplifier in the PGA is a pseudo-differential, positive-feedback input stage architecture with a common-mode feedforward (CMFF) technique. The common-mode feedback (CMFB) is provided once two OTAs are cascaded. Schematic-level simulation results show that the OTA maintains a -3-dB bandwidth of 550 MHz, while keeping the distortion HD3 at -60 dB for a 30-MHz, 850 mVpp high definition video signal. The 88 dB DC gain is distributed among four OTA stages and the overall, combined PGA achieves a signal-to-noise ratio of 63 dB. Due to only two stacked transistors, it achieves high output swing of ±0.85 V, 1240 V/μs slew rate while consuming 10.4 mW power.

  • 48.
    Aamodt, Edvard
    et al.
    RISE Research Institutes of Sweden, Säkerhet och transport, Brand och Säkerhet.
    Holmvaag, Ole Anders
    RISE Research Institutes of Sweden, Säkerhet och transport, Brand och Säkerhet.
    Sanfeliu Melia, Cristina
    RISE Research Institutes of Sweden, Säkerhet och transport, Brand och Säkerhet.
    Erfaringer med mobile vanntåkeanlegg installert i boliger2022Rapport (Övrigt vetenskapligt)
    Abstract [en]

    Experiences regarding personal protection water mist systems installed in dwellings. Personal protection water mist systems can produce a water mist that can cool down and limit a fire in a small area in a dwelling. The system is equipped with sensitive detectors which can activate the system in the early stages of the fire and limit the fire spread, and in some cases extinguish the fire. This gives more time for evacuation, which can be especially important for vulnerable people with risk factors, like impaired cognitive and physical functioning. The goal of this study has been to map the experiences in Norway regarding personal protection water mist systems, considering how the municipalities have experienced the work related to the systems and whether the systems have activated and saved lives. This will shed light upon whether mobile water mist systems are appropriate measures for vulnerable people in the society, and the risk factors that determine whether the measure is appropriate or not. This study has used literature studies, questionnaires, and interviews to map the experiences of personal protection water mist systems in Norway. The results showed that personal protection water mist systems installed in Norwegian dwellings have been activated in connection with fire outbreaks, and thus limited or extinguished the fire. This has saved lives on several occasions and reduced the damage potential. There are many people who have risk factors that make it appropriate to install a mobile water mist system in their home, but there are also exceptions. The risk factors that indicate that it is beneficial to install mobile water mist systems in Norwegian dwellings are - Impaired cognitive abilities - Impaired physical abilities - Drug and alcohol problems - Smoking - Living alone The systems are particularly suitable when several of the risk factors are present at the same time. It was also shown that personal protection water mist systems are not suitable for mobile people who spend time in several places in the home and are therefore often outside the system's coverage area. Personal protection water mist systems are not recommended for people who may have the potential to sabotage the system. In questionnaires and interviews, it emerged that there are big differences between how Norwegian municipalities work with assigning, installing, operating, and maintaining personal protection water mist systems. In larger municipalities, there are more people who rely on routines and formal processes for the work, and there is therefore a greater proportion of the larger municipalities who distribute the facilities out to individuals than in the small municipalities where the work is more characterised by informal routines and personal relations. 3 Based on the results from this study, it is our opinion that the following aspects should be covered by future work: • Need for a new and updated cost-benefit analysis for personal protection water mist systems. • Need for a better statistical basis for assessment of the personal protection water mist systems. • Need for a Norwegian test standard for personal protection water mist systems. • Need for clear guidelines for assignment, procurement, installing, operation, and maintenance of personal protection water mist systems.

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  • 49.
    Aamodt, Edvard
    et al.
    RISE Research Institutes of Sweden, Säkerhet och transport, Säkerhetsforskning.
    Meraner, Christoph
    RISE Research Institutes of Sweden, Säkerhet och transport, Säkerhetsforskning.
    Brandt, Are W
    RISE Research Institutes of Sweden, Säkerhet och transport, Säkerhetsforskning.
    Review of efficient manual fire extinguishing methods and equipment for the fire service2020Rapport (Övrigt vetenskapligt)
    Abstract [en]

    The late 90s and the early 2000s was a period with relative extensive research and innovation in the area of manual fire extinguishing methods and equipment for the fire service. New equipment such as the cutting extinguisher and extinguishing spears allowed to conduct offensive attacks from the exterior of a building, reducing the exposure of fire fighters to fire and smoke and their associated risks in general. This led to the development of new firefighting tactics, as for example the Quadrant Model of the Dutch fire service, which extends the “traditional” offensive interior attack and defensive exterior attack by the offensive exterior attack and defensive interior attack.Recently the research focus has furthermore increasingly shifted to environmental aspects, such as the water consumption and effect of additives (i.e., foam) on humans and the environment. Extinguishing with smaller amounts of water is beneficial for the environment, reduces water damage and lowers the burden on the water delivery system.ConclusionIn conclusion, the systems most relevant to be further tested in a fire situation in a small house or dwelling are the cutting extinguisher and the extinguishing spear.These systems are different in operation but have both shown to be promising with regard to fulfilling the different objectives of the overall project. Being relatively easy to utilize with the right training during internal extinguishing efforts executed from the outside of the building, and being only water based to minimize contamination, due to lower water consumption, of the surrounding areas give these systems advantages over conventional equipment.Especially if the systems are used in combination with an IR camera to locate the fire, the extinguishing efforts can be started early and effectively, and the water amount needed to control the fire may be reduced. The need for firefighters with breathing apparatus is reduced as well, hence reducing the smoke exposure to firefighters.The fact that the fire service also recognizes the potential of using these systems early in the extinguishing efforts, and is working on implementing them, prompts the need for scientific backup.

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  • 50.
    Aamodt, Edvard
    et al.
    RISE Research Institutes of Sweden, Säkerhet och transport, Brandteknik.
    Rønning, Birger
    RISE Research Institutes of Sweden, Säkerhet och transport, Brandteknik.
    Sikkerhetsbehov for kullgriller i restauranter2020Rapport (Övrigt vetenskapligt)
    Abstract [en]

    The RISE report 2019:04 «Charcoal and wood burning ovens in restaurants – Fire safety and documentation requirements» [1] investigated regulations and documental demands tied to charcoal and wood burning ovens in restaurants in Norway. A part of the conclusion in this report emphasized the need for, through physical testing, mapping whether existing test standards covers the safety requirements of charcoal ovens in restaurants. NS-EN 13240:2001 «Roomheaters fired with solid fuel. Requirements and test methods» [2] was chosen as a relevant test standard. Three test ovens (a closed test oven, a dummy oven and an open test oven) was produced at RISE Fire Research. Their construction with regard to insulation capabilities, materials and dimensions was based on existing charcoal ovens placed on the Norwegian marked. This was done to achieve an objective depiction of the issue, without the need for a specific brand of ovens. Restaurant oven charcoal was utilized to achieve as real heat development as possible in the test ovens. The test layout is based on NS-EN 12340:2001, with a test rigg constructed of two «safety walls», ceiling and floor attached with thermocouples. Temperatures from the test oven are registered in the safety walls at several positions according to a standardised grid, and in the ceiling and the floor each have one single measurement position measuring warmest point. Thermocouples in the chimney and exhaust duct measured the flue gas temperatures transported to the exhaust system. Four different tests were conducted, where the first one was a standardized safety test including the closed oven model. The second test was the same safety test setup with the dummy oven besides the closed oven. The dummy contained a built-in propane burner to simulate the heat load from a real oven. The purpose was to simulate two ovens placed next to each other. The third test was an overload test on the closed test oven with 150 % fuel load and higher refuelling frequency. The last test was a test of the open test oven. The safety test method described in NS-EN 13240:2001 is suitable to test the level of stable maximal temperature in the surrounding combustible materials, in the same way as for roomheaters, which the method is designed for. The method addresses safety aspects such as surface temperatures and handles on the oven. Tests show that the temperatures developed in the ovens have the potential to breech the temperature criterion given by the test standard, and therefore contribute to the ignition of surrounding combustible materials. Such situations pose a fire risk and safety measures regarding this aspect must be documented by the producer. NS-EN13240:2001 does not cover temperatures for exhaust duct and the production of sparks and their possible spread to combustible materials. These are important safety aspects which must be addressed when documenting the fire safety of restaurant grills. Tests show that sparks are created in the oven, including from restaurant charcoal fuel, and are transported into the exhaust duct, and out through the opening of the grill door. Together with high flue gas temperatures in the exhaust duct and deposits of soot and cooking oil this pose a fire risk. Documentation must therefore be presented, showing that the oven is equipped with measures (for instance spark screen) which guards the exhaust duct from sparks to a satisfactory degree. Operators of the oven must receive adequate training and must operate the closed oven with caution, as to avoid incidents with sparks being released though the door. The placement of ovens next to each other does not seem to increase the heat load on surrounding walls but may lead to increased temperatures in between the ovens. The consequences of temperature increases must be documented. Tests show that overloading with fuel and intensifying the refuelling intervals can lead to increased temperatures in the oven, which can affect materials and welding seams. Overloading can also affect the temperatures towards surrounding walls and exhaust ducts and therefore may affect fire safety negatively. NS-EN 13240:2001 requires the producer to documents how the oven is constructed and of what materials, and that the welding seams are dimensioned for the materials used. It is recommended that the producer documents the safety level of the oven materials with an overload test. It must also be documented that the exhaust ducts in which the flue gas are transported are constructed to handle the potential temperatures that can arise, including erroneous use.

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