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To mitigate climate change, greenhouse gas emissions must be reduced to net-zero in 2050 requiring a drastic transition in today´s energy sector. To achieve this goal, the use of biofuels produced from lignocellulosic feedstocks, including agricultural and forestry residues, is expected to play an important role. The native ability of the anaerobic thermophile Clostridium thermocellum to efficiently degrade lignocellulose makes this microorganism a promising candidate for consolidated bioprocessing of lignocellulosic feedstocks into the biofuel ethanol. However, improvements in ethanol yield, titre, and tolerance are required for industrial implementation. The aim of this thesis was to increase understanding of the central metabolism of C. thermocellum and thereby aid future metabolic engineering and process optimization efforts focused on improving ethanol production from lignocellulosic material. The atypical glycolysis of C. thermocellum uses pyrophosphate (PPi) instead of ATP as phosphoryl donor. This alteration is hypothesized to increase energetic efficiency but simultaneously decrease thermodynamic driving force resulting in lower achievable ethanol titres. As such, improved understanding of the PPi metabolism has both fundamental and applied importance. Knockout studies combined with physiological characterization of four predicted metabolic PPi sources provided valuable insights into the PPi metabolism and demonstrated that the energetic benefits of PPi usage are likely limited. Furthermore, biochemical characterization of the ATP-Pfk from C. thermocellum and other bacteria demonstrated that PPi might be a key allosteric regulator in bacteria with a PPi-dependent glycolysis. The low thermodynamic driving force of the ethanol formation pathway combined with a flexible redox network are key factors that impact ethanol titre, yield, and tolerance in C. thermocellum. Apart from dominant thermodynamic limitations, physiological characterization of wild-type and a non-ethanol producing mutant at various exogenous ethanol concentrations and temperatures demonstrated that biophysical limitations also impact ethanol tolerance. Lowering the cultivation temperature decreased chaotropic effects of ethanol and improved ethanol tolerance. By-product formation and incomplete substrate utilization decrease obtained ethanol yields. To minimize formation of one specific class of by-products, the mechanism behind amino acid secretion in C. thermocellum was investigated. Cellobiose- or ammonium-limited chemostats of wild-type and knockout strains of NADPH-supplying and NADPH-consuming pathways identified catabolic oversupply of NADPH as the main driver behind amino acid secretion. The malate shunt and the ammonium-regulated shift between nitrogen assimilation pathways with differing cofactor specificities were shown to play key roles in NADPH metabolism and amino acid secretion. To improve substrate utilization, laboratory evolution combined with reverse metabolic engineering was used as a tool to provide insights into increased utilization of glucose and fructose. Reproducible and constitutive growth on these hexose sugars was achieved for evolved mutant strains. Additionally, two mutations were identified that are involved in (regulation of) transport or metabolism of these hexose sugars. Together these findings provide valuable insights into the central metabolism of C. thermocellum and aid future optimizations of this organism for consolidated bioprocessing of lignocellulosic feedstocks into fuels and chemicals. För att mildra klimatförändringarna måste utsläppen av växthusgaser minskas till nettonoll år 2050 vilket kräver en drastisk förändring i dagens energisektor. För att uppnå detta mål förväntas användningen av biobränslen producerade från lignocellulosabaserade råmaterial, såsom jordbruks- och skogsrester, spela en viktig roll. Den naturliga förmågan att effektivt bryta ned lignocellulosa hittas hos den anaerobiska termofilen Clostridium thermocellum och gör denna mikroorganism till en lovande kandidat för konsoliderad bioprocessering av lignocellulosabaserade råmaterial till biobränslet etanol. För industriell implementering krävs dock förbättringar av etanolutbyte, -titer och -tolerans. Syftet med denna avhandling var att öka förståelsen av C. thermocellums centrala metabolism och därigenom vägleda framtida insatser inom metabol ingenjörskonst och processoptimering för att förbättra etanolproduktionen från lignocellulosabaserade råvaror. Den atypiska glykolysen hos C. thermocellum använder pyrofosfat (PPi) i stället för ATP som fosforyldonator. Denna skillnad har hypotiserats öka energieffektiviteten men samtidigt minska den termodynamiska drivkraften, och resultera i en lägre uppnåbar etanoltiter. Därför är en förbättrad förståelse av PPi-metabolismen viktig ur fundamentala och applicerbara perspektiv. Knockoutstudier tillsammans med fysiologisk karaktärisering av fyra predikterade metaboliska PPi-källor gav värdefulla insikter i PPi-metabolismen och visade att energifördelarna med användningen av PPi sannolikt är begränsade. Vidare visade biokemisk karaktärisering av ATP-Pfk från C. thermocellum och andra bakterier att PPi kan vara en viktig allosterisk regulator för bakterier med en PPi-beroende glykolys. Den låga termodynamiska drivkraften hos etanolproduktionsvägen kombinerat med ett flexibelt redoxnätverk är nyckelfaktorer som påverkar etanoltitern, -utbytet och -toleransen hos C. thermocellum. Förutom övervägande termodynamiska begränsningar visade fysiologisk karaktärisering av vildtypen och en modifierad icke-etanolproducerande stam, vid olika extracellulära etanolkoncentrationer och temperaturer, att även biokemiska begränsningar påverkar etanoltoleransen. Att sänka odlingstemperaturen reducerade de kaotropiska effekterna av etanol och förbättrade etanoltoleransen. Produktion av biprodukter och ofullständigt substratutnyttjande minskar erhållna etanolutbyten. För att minimera produktionen av en specifik klass av biprodukter undersöktes mekanismen bakom aminosyrasekretion hos C. thermocellum. Cellobios- eller ammoniumbegränsade kemostater av vildtypen och knockout-stammar av NADPH-producerande och -konsumerande reaktionsvägar identifierade ett katabolisk överskott av NADPH som den främsta drivkraften bakom aminosyrasekretion. Malatshunten samt det ammoniumreglerade skiftet mellan olika assimileringvägar av kväve med specificitet för olika kofaktorer visade sig spela en nyckelroll i NADPH-metabolismen och aminosyrasekretionen. För att öka substratutnyttjandet användes laboratorieevolution kombinerat med reverse metabolic engineering som verktyg för att ge insikter i hur utnyttjande av glukos och fruktos kan förbättras. Laboratorieevolutionen resulterade i stammar med reproducerbar och konstitutiv tillväxt på dessa hexoser. Sedan identifierades två mutationer involverade i (reglering av) transport eller metabolism av dessa hexoser. Tillsammans ger dessa forskningsrön värdefulla insikter i C. thermocellums centrala metabolism och underlättar framtida optimeringar av denna organism för konsoliderad bioprocessering av lignocellulosabaserat råmaterial till bränslen och kemikalier. QC 2023-04-25

Phase change phenomena of a fluid flowing in a micro channel may be exploited to make the heat exchangers more compact and energy efficient. Compact heat exchangers offer several advantages such as light weight, low cost, energy efficiency, capability of removing high heat fluxes and charge reduction are a few to mention. Phase change phenomena in macro or conventional channels have been investigated since long but in case of micro channels, fewer studies of phase change have been conducted and underlying phenomena during two-phase flow in micro channels are not yet fully understood. It is clear from the literature that the two-phase flow models developed for conventional channels do not perform well when extrapolated to micro scale. In the current thesis, the experimental flow boiling results for micro channels are reported. Experiments were conducted in circular, stainless steel and quartz tubes in both horizontal and vertical orientations. The internal diameters of steel tubes tested were 1.70 mm, 1.224 mm and the diameter of quartz tube tested was 0.781 mm. The quartz tube was coated with a thin, electrically conductive, transparent layer of Indium-Tin-Oxide (ITO) making simultaneous heating and visualization possible. Test tubes were heated electrically using DC power supply. Two refrigerants R134a and R245fa were used as working fluids during the tests. Experiments were conducted at a wide variety of operating conditions. Flow visualization results obtained with quartz tube clearly showed the presence of confinement effects and consequently an early transition to annular flow for micro channels. Several flow pattern images were captured during flow boiling of R134a in quartz tube. Flow patterns recorded during the experiments were presented in the form of Reynolds number versus vapour quality and superficial liquid velocity versus superficial gas velocity plots. Experimental flow pattern maps so obtained were also compared with the other flow pattern maps available in the literature showing a poor agreement. Flow boiling heat transfer results for quartz and steel tubes indicate that the heat transfer coefficient increases with heat flux and system pressure but is independent on mass flux and vapour quality. Experimental flow boiling heat transfer coefficient results were compared with those obtained using different correlations from the literature. Heat transfer experiments with steel tubes were continued up to dryout condition and it was observed that dryout conditions always started close to the exit of the tube. The dryout heat flux increased with mass flux and decreased with exit vapour quality. The dryout data were compared with some well known CHF correlations available in the literature. Two-phase frictional pressure drop for the quartz tube was also obtained under different operating conditions. As expected, two-phase frictional pressure drop increased with mass flux and exit vapour quality. QC 20101206

This PhD thesis in Spatial Planning argues for the importance of understanding the approaches to knowledge and rationalities embedded in spatially relevant decision-making. It emphasises the significance of seeing law as an empirical object of study for planning and environmental management. The Swedish development of wind power and 3G mobile infrastructures are used as cases to study these issues of principal interest. It is a compilation thesis consisting of a comprehensive introductory framework and five articles or chapters that have also been published elsewhere. The study is based on three main perspectives: Level of decision-making, legitimacy of different forms of knowledge involved in the process, and the sociolegal tension between formal law and its practical consequences. The thesis deals with problems stemming from the multi-level tensions in the planning and implementation that exist between the national, the regional and the local authorities. The legal context is analysed from the sociolegal perspective, in particular how the juridification of siting and permit conflicts determines what type of knowledge that can legitimately affect the decision-making and thereby set conditions for public participation. Finally, the thesis elaborates on the largely counterproductive results of the strong emphasis on “efficiency” in the revision of planning and permit processes for wind power and 3G-infrastructure, and what can be learnt from the experiences of the attempts at increasing efficiency. A combination of methods has been employed in the studies, and the data comes from a range of sources such as a large set of mast building permits, a sample of wind permit cases, as well as appealed permit cases. In addition, interviews have been conducted with judges from relevant courts, including regional handling officers who assess wind turbine applications. Legal documents such as preparatory work and licence conditions have also been analysed. The results show that there is a legal-rhetorical adaptation to the expert-based decision-making in court when permits are appealed. Further, the administrative levels interact poorly in the overall implementation. The national decisions, irrespective of the normative viewpoint of who should control the landscape planning, could be better informed of the preconditions at a local level that factually define the outcome of the implementation. The author, Stefan Larsson, holds a PhD in Sociology of Law, an LLM and is a sociolegal researcher who generally studies issues in the intersection of conceptual, sociolegal and technological change. The thesis has been supervised by Professor Lars Emmelin, The Swedish School of Planning, BTH, and co-supervised by Professor Karsten Åström, the Department of Sociology of Law, Lund University. The thesis is the result of research within the programme Tools for environmental assessment in strategic decision-making, MiSt, funded by The Swedish Environmental Protection Agency and the Centre for Work, Technology and Social Change at Lund University. Denna sammanläggningsavhandling i fysisk planering visar hur viktig rättens och juridikens roll är för planeringen och styrning av landskap och miljö, och de fall som studerats och analyserats är den svenska utbyggnaden av 3G-infrastruktur och vindkraften. Utifrån ett rättssociologiskt planeringsperspektiv visar Stefan Larsson (som också disputerat i rättssociologi tidigare) på hur implementering och planering av denna specifika typ av infrastruktur kunde förbättras med ett mer empiriskt förhållningssätt till rätten, rättsliga förändringar och dess konsekvenser. Avhandlingen består av en relativt omfattande kappa som summerar och mer helhetsmässigt analyserar fem efterföljande vetenskapliga artiklar. Tre genomgående perspektiv styr upplägg och analys: Nivåer i beslutsfattandet; legitimiteten hos olika kunskapstyper; och skillnaden mellan det formella upplägget och det praktiska utfallet. Genom att samla in och gå igenom en stor mängd bygglov för 3G-master, ett urval av miljötillstånd för vindkraft som överklagats, intervjuer med nyckelaktörer samt lagstiftningsförändringar visar Larsson på hur en rättsligt retoriska tillvänjning sker vid överklagandeärenden, hur expertbaserad kunskap övertrumfar lekmannakunskap, och hur de olika samhällsnivåerna kunde interagera och informera varandra bättre i planering och implementering av nämnda typ av infrastrukturer.

The industrial sector accounts for almost 40 % of the Swedish energy use and in order to meet the EU’s 2020 targets, an efficient production of high quality and great finish goods are more and more in demand. Moreover, it is important to develop the activities with the lowest environmental impact possible. The energy audit process is an effective tool to achieve it. Thus, in this document the energy audit of an industrial company, Automat Industrier in Gävle, Sweden, was carried out. The energy balance of the building and the potential energy efficiency measures were analyzed with the IDA ICE simulation. The proposed energy retrofitting was apropos of the building envelope, the lighting system, the ventilation system and the installation of a PV system on the roof of the building. The survey indicated that the potential energy savings of the company accounted for 62.5 % of the current electricity use and 48.8 % of the current DH use if all the proposed ameliorations were performed. The main promoter of the electricity savings is the installation of the PV system, with 85 % of influence. Almost 90 % of the DH savings are due to the measures in the ventilation system. Financially, these savings can reach the amounts of 531 597 SEK/year for electricity and 174 201 SEK/year for DH. Nevertheless, the ameliorations regarding the building envelope have very long payback periods. Thus, it was recommended to not pursue them. Fortunately, the energy efficiency measures providing the greatest savings’ payback periods are between 3.47 years and 10.22 years long. As they are independent from each other, the owner has the freedom to decide whether to apply them or not and when if so.

Efficient use of resources and sustainable recovery of various materials are important to minimize the anthropogenic impact on the climate and environment. One such resource is the phosphorus (P) present in manure and sewage sludge. Various technologies are currently being developed to recover the element for application as fertilizer in agricultural applications. Thermochemical conversion presents the opportunity to recover energy from these materials. In a single process, elements can be recovered in ash fractions, potentially harmful organic substances can be destroyed and heavy metals fractionated from the P. Mono-combustion of sewage sludge mainly produce apatite, a phosphate mineral with low plant availability and therefore less useful for fertilization. Co-combustion/-gasification with other fuels enables modification of the ash transformation reaction pathways and remedies potential problems, such as bed agglomeration, associated with forestry and agricultural residues when used as fuels. The overall objective of this work was to increase the current knowledge in ash transformation of P-rich materials in co-conversion with forestry and agricultural residues in order to facilitate the P-recovery by formation of suitable phosphates in the ash. The work focuses on i) the influence of co-conversion on ash transformation of P with a focus on altering speciation of P towards the potentially more plant-available K-bearing phosphates ii) the influence of fuel ash composition and chemical association of P in the fuel, temperature and particle interaction on the fate, i.e. speciation and distribution, of P and iii) practical implications of co-conversion in fluidized bed and pulverized fuel systems for P-recovery, specifically interaction of P-rich ash with bed material in fluidized beds and strategies for extracting P-rich ashes. Experiments were carried out in a bench-scale bubbling fluidized bed reactor (BFB), macro-thermogravimetric analysis (TGA) conversion reactor, a dual fluidized bed (DFB) gasification reactor, and an entrained flow reactor (EFR) for pulverized fuel combustion. The fuels studied were mixtures of chicken litter together with wheat straw and bark, and mixtures of digested sewage sludge combined with wheat straw and sunflower husk. The process temperature ranges studied were 800-950 °C for BFB and single-pellet macro-TGA studies, whereas 1000 °Cand 1400 °C were investigated in pulverized fuel combustion studies using the EFR. Ash fractions and bed materials were collected and analyzed using scanning electron microscopy with energy-dispersive Xray spectroscopy (SEM-EDS), powder X-ray diffraction (XRD), inductively coupled plasma with atomic emission spectroscopy (ICPAES) and ion chromatography (IC). The results were interpreted with the support of thermodynamic equilibrium calculations (TECs) using FactSage software with the GTOX & SGPS databases. For all investigated conditions and fuel mixtures, the major part of P (> 90 %) was found in coarse ash fractions, suggesting that the recovery potential is highest in these fractions. This also means that P and volatile heavy metals can be separated in different ash fractions. Crystalline P was to a higher degree observed in the form of K-bearing whitlockite structures and CaKPO4 in mixtures containing low amounts of sewage sludge and high amounts of agricultural residues rich in K. K-bearing whitlockites were also found in ash of chicken litter and its mixture with wheat straw, as well as in ash deposits formed in pulverized combustion with a sewage sludge and wheat straw mixture combusted at 1000 °C. In mixtures with higher shares of sewage sludge, crystalline P was mainly found as Fe- and Mg-substituted whitlockites and hydroxyapatite. The reaction pathway of P appears to mainly occur through substitution and addition reactions in the condensed phase. The findings show that it is possible to modify the ash transformation of P towards K-bearing phosphates by co-conversion and that the difference between combustion and gasification is small. For the mixture of chicken litter and K- and Si-rich wheat straw combusted in BFB, P and Si together with K and Ca formed homogeneous ash particles with large amounts of potentially amorphous content. A similar behavior was observed in sewage sludge and wheat straw mixtures, where P and Si were likely present in a melt that was amorphous after extraction. In addition to these particles, P was also observed in crystalline orthophosphate compounds such as hydroxyapatite, aluminium phosphate, whitlockites and CaKPO4. In the mixture of chicken litter with Ca-rich bark, crystalline P was found in the form of hydroxyapatite. In fuel mixtures with higher amounts of Al with Si, the capture of K in aluminosilicates was higher, making it unavailable to form K-bearing phosphates. Small differences in the fate of P, between organically and inorganically associated P found in the fuels were seen in this work. Lower temperatures (800 °C compared to 950 °C) favored the formation of crystalline K-bearing phosphates in single-pellet combustion of sewage sludge and agricultural residues. In pulverized fuel combustion experiments, more crystalline K-bearing phosphates were found at 1000°C compared to 1400 °C. Fuel ash interaction mainly occurred in condensed phases in ash deposits compared to interactions between particles entrained in the flow. In fluidized bed experiments, P captured Ca and K in relatively high temperature melting phosphates in the fuel ash, decreasing the interactions of these elements with the bed material and thus decreased the risk for bed agglomeration. Possible extraction strategies involve the separation of coarse ash particles from bed material particles or in heated cyclones, avoiding fine ash fractions known to be rich in volatile heavy metals. Mixtures of coarse ash and bed material can potentially also be used for P-recovery. Co-conversion increases the possibility of utilizing existing boilers for recovery of P and increasing their flexibility to different fuels. The results indicate that a powder combustor operating in slagging mode could be a feasible strategy for P recovery because the interaction potential between the formed individual coarse ash particles increases at the hot wall. Plant growth studies have to be performed to further validate the agricultural value of the produced ashes for direct soil application.

Marginalisering gällande tillgång till elektricitet utgör en betydande utmaning i avlägsna områden i Peru. Elnätets stabilitet är låg och detta utgör ett hot mot viktig infrastruktur såsom sjukhus och vårdcentraler. Enligt Världshälsoorganisationen förloras 50 % av alla vacciner världen över på grund av felaktig hantering där strömavbrott är en viktig del av problemet. Syftet med denna studie var att öka energitåligheten hos ett medicinskt center i Talara i norra Peru. För att uppnå detta mål utfördes teknisk dimensionering av ett avbrottsfritt strömförsörjningssystem (UPS) bestående av solceller och batterier. Två kvalitativa intervjuer med en eldistributör i norra Peru och en tillsynsmyndighet gjordes för att fördjupa kunskapen om vilka utmaningar som finns gällande elnätets tillförlitlighet. Två scenarier utvärderades i dimensioneringen av UPS systemet. Scenario 1 presenterar den ursprungliga planen av EcoSwell som inkluderar all utrustning som var avsedd att strömförsörjas av UPS systemet, medan scenario 2 är en reducerad version av scenario 1 för att minska de totala kostnaderna. För scenario 1 kommer totalt 36 batterier och 48 solceller att krävas för att försörja all utrustning med energi. I scenario 2 kommer 20 batterier och 24 solceller att behövas. OMP Solar blev den utvalda leverantören av solceller och batterier och den totala kostnaden för installation och all extrautrustning är 66 713,98 S/ (184 036 SEK). Det uppskattades att 37 % och 17 % för scenario 1 respektive 2 av den totala energianvändningen vid vårdcentralen kommer att utgöras utav UPS systemet. Marginalization in terms of electricity access presents a significant challenge in remote areas in Peru. The resilience of the electric grid is low, and this presents a threat to important infrastructure such as hospitals and medical centers. According to the World Health Organization, 50% of vaccines worldwide are wasted due to improper handling in which power cuts is a major problem. The aim of this study was to increase the energy resilience of a medical center located in Talara in northern Peru. In pursuit of this aim, technical sizing of an uninterruptable power supply (UPS) system consisting of photovoltaic modules and lead-acid gel batteries was done. Two qualitative interviews with an electricity distributor in northern Peru and a supervisory authority was made to deepen the knowledge of what challenges exist regarding the reliability of the electric grid. Two scenarios were evaluated in the sizing of the UPS. Scenario 1 presents the original plan by EcoSwell including all equipment that was intended to be powered up by the UPS, while scenario 2 is a reduced version of scenario 1 to decrease overall costs. For scenario 1 a total of 36 batteries and 48 solar modules will be required to power up all equipment. In scenario 2, 20 batteries and 24 solar modules will be required. OMP Solar was the chosen provider of solar modules and batteries and the total cost for installation and all auxiliary equipment is 66 713,98 S/ (184 036 SEK). It was estimated that 37% and 17% for scenario 1 and 2 respectively of the total energy usage at the medical center will be from the UPS. 

The sustainability challenges of our time require engagement from all, and the potential for the arts and humanities to contribute has been undervalued and underutilized within sustainability science approaches. UNESCO sees education is seen as a key leverage point to shift society towards sustainability transformations however as with sustainability approaches in general, the potential of creativity and the arts remains untapped as a tool, topic, process, pedagogy and way of thinking. Inspired by a creativity assignment delivered in a Leadership in Sustainability course at Curtin University in Western Australia, this paper describes a Creativity in Action Project which was an assignment within the Advanced Leadership for Sustainability course at Blekinge Institute of Technology in Sweden. It was a year long course that ran through 2021. This paper articulates the purpose, design, pedagogy, content and learning process of the Creativity in Action Project and how it integrates the whole course. In brief, the students were invited to: “...explore the role creativity and/or the arts play, or could play, in expanding your thinking and in shifting paradigms that move people towards sustainability” and the intention of the project was to “...explore creative ways to enact change for sustainability in your lives or communities” through taking inspiration from artistic practices and processes. Through a feedback survey from the students, this study evaluates the project as a whole and identifies the key pedagogical elements that supported the students learning; what provided value and impact for the students; as well as discussing the challenges in doing such work. With permission from the students, this paper showcases some of the artistic and creative projects that the students completed. The intention of this paper is to provide educators and learning designers with inspiration and a practical, adaptable, and impactful creativity-based pedagogy for the development of sustainability leadership and key sustainability competencies that could be used and adapted to various contexts. It is hoped this will in turn support societal transition towards sustainability through empowering students to be sustainability change agents by applying their creativity to solve a sustainability challenge in real life.

As society becomes increasingly digitalised, pressure is put on public organisations to keep up with technological developments. Thus, digital transformations, which is a strategic relocation of the business, have become essential for organisations. Digital transformations are associated with complexity and a high failure rate, partly due to organisational barriers and the necessity of structural changes and possessing several dynamic capabilities. Private organisations have led the way in the era of integrating technology with business, and public organisations have attempted to follow. As a result, governing inspired by private organisations have been developed for public organisations, namely new public management. However, this governing does not cover values essential for public organisations, e.g., public value, nor facilitating digital transformations. Governance that enables adaptation and responsiveness as well as creating public value is necessary, e.g., adaptive and agile governance. This thesis aims to investigate digital transformation in public organisations and the effect governing principles have on it. The study also explores the potential of adaptive governance and if digitalisation can enable municipalities to work with sustainability. To answer this, an exploratory study is conducted, which includes a case study, and a framework is constructed based on a literature review together with four in-depth interviews with scientists. The framework is then applied to the case study, consisting of 11 semi-structured interviews. The findings indicate that digital transformations of public organisations can be conducted without considering governing principles. However, governance can affect how successful the transformation is and what value creation it can bring. Using governance that does not facilitate the transformation could impact its success. Adaptive governance can solve many issues in municipal digital transformations, but may not solely be the solution. It emphasises learning and trial and-error and observes the transformation through an ecosystem perspective. However, the practical implications of it are limited as no methods exist. Thus, combinations with other governing principles may be required. Additionally, digitalisation cannot enable municipalities to achieve sustainability aims on its own. Instead, digital technologies are tools that the municipality can use to achieve sustainability. The study contributes to research by investigating the effect governing principles has on digital transformations of public organisations in a Swedish context, which previously was lacking. The framework can provide a guide and analysis tool for public organisation’s digital transformation, and shows potential to be applied in practice. När samhället blir alltmer digitaliserat pressas offentliga organisationer att hålla jämna steg med den tekniska utvecklingen. Således har digitala transformationer, som är en strategisk förflyttning av verksamheten, blivit väsentligt för organisationer. Digitala transformationer är förknippade med komplexitet och hög andel misslyckanden, delvis på grund av nödvändiga strukturella förändringar och innehav av flertalet dynamiska kapaciteter, såväl som organisatoriska hinder. Privata organisationer har lett vägen i att integrera teknik med verksamheten och offentliga organisationer har försökt följa med. Detta har resulterat i att styrningen av offentliga organisationer inspirerats av näringslivet, nämligen new public management. Denna styrning täcker dock inte värden som är viktiga för offentliga organisationer, t.ex. offentligt värde, eller underlättar digitala transformationer. Styrning som möjliggör anpassning och lyhördhet samt skapar offentligt värde är nödvändigt, exempelvis adaptiv och agil styrning. Denna uppsats syftar till att undersöka digitala transformationer i offentlig sektor och vilken effekt styrande principer har på det. Studien undersöker också potentialen för adaptiv styrning och om digitalisering kan göra det möjligt för kommuner att arbeta med hållbarhet. För att svara på detta genomförs en undersökande studie, som inkluderar en fallstudie, och ett ramverk skapas baserat på en litteraturgenomgång tillsammans med fyra djupintervjuer med forskare. Ramverket tillämpas sedan på fallstudien, bestående av elvasemistrukturerade intervjuer. Resultaten tyder på att digitala transformationer av offentliga organisationerkan genomföras utan att ta hänsyn till styrande principer, men styrningen kan påverka hur optimal transformationen är och vilket värdeskapande den kan ge. Att använda styrning som inte underlättar transformationen kan påverka hur framgångsrik den är. Adaptiv styrning har förmågan att lösa många problem som finns i kommunala digitala transformationer, men är inte enskilt lösningen. Den betonar lärande och experimenterande samt observerar transformationen ur ett ekosystemsperspektiv. De praktiska implikationerna av den är dock begränsade, då den inte innehar specifika metoder. Således kan kombinationer med andra styrande principer krävas. Därtill medför inte digitalisering att kommuner uppnår hållbarhetsmål på egen hand. Istället bör digital teknik ses som verktyg som kommuner kan använda för att uppnå hållbarhet. Studien bidrar till forskning genom att undersöka vilken effekt styrande principer har på digital transformation inom offentliga organisationer ur ett svenskt perspektiv, vilket saknas i tidigare forskning. Ramverket kan tillhandahålla ett guide- och analysverktyg för offentliga organisationers digitala transformation och visar potential att kunna användas i praktiken.

Harmonic studies in almost all cases are limited to the frequency range up to 2 or 2.5 kHz. In the frequency range above 2 kHz, almost no standards exist and measurements are rare. This paper presents measurements of the emission from a total installation in the frequency range 2 to 150 kHz. A physical model (electrically full-scale) of a domestic customer was built in the laboratory. Field measurements were performed on a medium-sized hotel. The impact of different types of lighting is shown to be small. Validerad; 2011; 20110613 (ronsar)

At the beginning of the 20th century the pulp industry in Sweden faced major problems with waste. Pine and spruce contain at the best 40 % cellulose. The remainder was released into the air and water, causing major environmental problems. In 1909 two Swedish engineers patented a method to ferment sulphite lye into alcohol. Apart for consumption, the alcohol could be used as fuel. The rest of the lye, reduced of it’s saccariferous contents, was expected to become the basis of a new chemical industry, producing dyestuffs etc. Within two years three sulphite alcohol factories were established in Sweden and the method was also used in other countries. There was just one problem. In Sweden, ever since the beginning of the 17th century, the production of liquor had been intensely regulated by the state. And the law concerning the production was adapted to agrarian interests, producing alcohol from products like corn or potatoes. Organized temperance and the agrarians acted against the pulp producers and argued that it’s better to use “natural” products instead of dirty lye. Then came the First World War and the import of petrol decreased. At the same time food supply became critical. It seemed unreasonable to produce alcohol out of food, but reasonable to compensate the lack of petrol with sulphite alcohol- The number of plants producing sulphite alcohol grew rapidly and an industry producing car engines fuelled by sulphite alcohol was emerging. This came to an end after the war when the price of imported petrol gave sulphite alcohol problems to compete and agrarian and temperance interests once again acted against the production. But the story was repeated during the Second World War and is also of contemporary interest since many countries and companies are trying to substitute oil for ethanol, bio-alcohol