Att koldioxidutsläppen neutraliseras är avgörande för att begränsa klimatförändringarna. Bioenergi i kombination med separation och lagring av koldioxid (BECCS) är en Teknik som kan generera negativa utsläpp. Det största hindret för dess storskaliga genomförande är de höga energikraven för processen. Detta projekt syftar till att kvantifiera energistraffen för lean solvent flash och modifikationer för multitrycksstrippning för att förbättra prestandan av koldioxidavskiljning (CC) i en kraftvärmeverksanläggning för förbränning av biomassa.  En jämviktsmodell utvecklades och validerades för att simulera en fullskalig CC genom kemisk absorption i Aspen Plus med kaliumkarbonat som lösningsmedel. Båda layoutändringarna resulterar i energipåföljder på 18-21 % för en kraftvärmeverk, medan energistraffet för baslinjeprocessen är 5 %. För ett kraftverk går straffen från 32 till 62 %. Detta visar hur en förbättring av processen kan minska kostnaderna för CCS, särskilt om värme anses vara en värdefull produkt. CCS i kraftvärmeverk har en mycket lägre energipåverkan än i kraftverk där värme inte återvinns. / Bio-energy with carbon capture and storage (BECCS) is a technology that can generate negative emissions. Hence it is recognized as a solution for becoming carbon neutral, which is essential for climate change mitigation. The main obstacle for its large scale implementation is the high energy requirements of the process. This thesis aims at quantifying the energy penalties for lean solvent flash and multi-pressure stripper layout modifications to improve the performance of carbon capture (CC) by means of absorption with a liquid solvent in a biomass-fired CHP plant. The work focuses on K2CO3 based solvents operated in a mixed temperature swing/pressure swing cycle witch is deemed advantageous for heat recovery.  An equilibrium model was developed and validated to simulate a full-scale CC by chemical absorption in Aspen Plus using potassium carbonate as solvent. Both layout modifications result in energy penalties of 18-21 % for a CHP plant, while the energy penalty for the baseline process is 28 %. For a power plant, the penalties go from 32 % to 62 % for the lean solvent flash and the multi-pressure stripper respectively. This shows how improving the process can reduce the costs of CCS, especially if heat is considered a valuable product. CCS in CHP plants has a much lower energy impact than in power plants where heat is not recovered.

CO2 capture and storage (CCS) is estimated to reduce 14% of the global CO2 emissions in the 2 °C scenario presented by the International Energy Agency. Moreover, post combustion capture is identified as a potential method for CO2 capture from industry since it can be easily retrofitted without disturbing the core industrial process. Among the post-combustion capture methods, absorption using mono-ethanol amine (MEA) is the most mature technology that has been demonstrated at plant scale. However, using chilled ammonia process as a post combustion capture technology in a cement industry can reduce 47% energy penalty for CO2 capture when compared to the conventional MEA absorption method.  Hence, the current project aims at analyzing the chilled ammonia process when integrated with steel and ammonia plants. Key performance indicator like specific primary energy consumption per kilogram of CO2 avoided (SPECCA) is estimated and compared with MEA absorption method. Firstly, chilled ammonia process (CAP) for cement plant was used as reference case. Then, CAP for steel and ammonia processes was optimized by the means of the decision variables affecting the capture and energy efficiency. The energy consumption per kg CO2 captured and SPECCA was lower for the higher CO2 concentration in the flue gas. Results for SPECCA were 3,56, 3,52 and 3,61 MJ/kg CO2 for cement, steel, and ammonia plants, respectively.

Bakgrund: Donation efter primär hjärnskada (DBD) har utförts i Sverige sedan 1981 och ärden vanligaste formen av donation. Donation efter cirkulationsstillestånd (DCD) infördes iSverige 2020 och ökar i omfattning. I länder där DCD redan är etablerat beskrivskunskapsnivån som låg i förhållande till DBD vilket leder till en känsla av otrygghet hosvårdpersonalen.Syfte: Att kartlägga hur intensivvårdssjuksköterskans skattar sina kunskaper och erfarenheter ivården av potentiella donatorer över 18 år enligt DCD processen.Metod: Enkätundersökning med kvantitativ design genomfördes. Enkäten skickades ut till 11intensivvårdsavdelningar i Sverige.Resultat: Består av svar från 58 respondenter. Majoriteten av respondenterna har fått teoretiskoch praktisk utbildning i att vårda en potentiell donator i DCD processen. Över 50% svararockså att de fått utbildning i att stödja donatorns närstående. Samband finns mellan kunskapoch utbildning men även mellan utbildning och skattad trygghet.Konklusion: Tydliga samband ses i studien mellan utbildning och kunskap. Kunskapen i sintur visar tydliga samband med intensivvårdssjuksköterskans skattade erfarenhet av trygghet ivården av den potentiella donatorn men även erfarenheten av att stödja/bemöta och besvarafrågor från närstående. Utbildningen är en viktig faktor för att förberedaintensivvårdssjuksköterskan i vården av en DCD. / Background: Donation after brain death (DBD) has been performed in Sweden since 1981 andis the most common type of donation. Donation after circulatory death (DCD) was introducedin Sweden in 2020 and is increasing in scope. In countries where DCD already is establishedthe level of knowledge is described as low in relation to DBD which leads to a feeling ofinsecurity of healthcare professionals.Purpose: To map how intensive care nurses estimate their knowledge and experiences in thecare of potential donors over the age of 18 according to the DCD-process.Method: Survey study with a quantitative design. The Survey was sent to eleven intensive careunits in Sweden.Result: Consist of answers from 58 respondents. The majority of the respondents receivedtheoretical and practical education in the care of a potential donor in the DCD process. Morethan 50% also received education to support the donors’ relatives. Correlations were shownbetween knowledge and education but also between education and a feeling of security.Conclusion: A clear correlation is seen in the study between education and knowledge.Knowledge in turn shows correlation to the intensive care nurse ́s valued experience in the careof a potential donor but also to the experience of supporting and answering questions from itskin. Education is an important factor to prepare the intensive care nurses in the care of a DCD.

This paper describes a unique method for the semi-automatic detection of historic charcoal production sites in LiDAR-derived digital elevation models. Intensified iron production in the early 17th century has remarkably influenced ways of how the land in Sweden was managed. Today, the abundance of charcoal kilns embedded in the landscape survives as cultural heritage monuments that testify about the scale forest management for charcoal production has contributed to the uprising iron manufacturing industry. An arbitrary selected study area (54 km2) south west of Gävle city served as an ideal testing ground, which is known to consist of already registered as well as unsurveyed charcoal kiln sites. The proposed approach encompasses combined morphometric classification methods being subjected to analytical image processing, where an image that represents refined terrain morphology was segmented and further followed by Hough Circle transfer function applied in seeking to detect circular shapes that represent charcoal kilns. Sites that have been identified manually and using the proposed method were only verified within an additionally established smaller validation area (6 km2). The resulting outcome accuracy was measured by calculating harmonic mean of precision and recall (F1-Score). Along with indication of previously undiscovered site locations, the proposed method showed relatively high score in recognising already registered sites after post-processing filtering. In spite of required continual fine-tuning, the described method can considerably facilitate mapping and overall management of cultural resources.

Heart failure is a growing public health problem associated with significant morbidity and mortality. Family support positively affects outcomes for the person with heart failure while also leading to caregiver burden. Registered nurses have a key role in supporting and meeting the needs of family caregivers. The overall aim was to explore the situation and needs of family caregivers to a person with heart failure, and explore requisites and ways of supporting and involving family caregivers in heart failure nursing care. Two interview studies, one web survey study and one intervention study were conducted between 2012 and 2017. A total of 22 family caregivers, eight persons with heart failure and 331 registered nurses participated in the studies. Family caregivers' daily life was characterized by worry, uncertainty and relational incongruence but salutogenic behaviours restored new strength and motivation to care. Family caregivers experienced that their caregiving was taken for granted by health care professionals. Family caregivers expressed a need for a permanent health care contact and more involvement in the planning and implementation of their near one’s health care together with health care professionals. Registered nurses acknowledged family caregivers’ burden, lack of knowledge and relational incongruence. A registered nurse was suggested as a permanent health care contact to improve continuity and security. Registered nurses neither acknowledged family caregivers as a resource nor their need for involvement. Registered nurses working in primary health care centres, in nurse-led heart failure clinics, with district nurse specialization, with education in cardiac nursing care held the most supportive attitudes toward family involvement in heart failure nursing care. Family health conversations via telephone in nurse-led heart failure clinics were found to successfully support and involve families. The conversations enhanced nurse-family relationship and relations within the family. They also provided registered nurses with new, relevant knowledge and understanding about the family as a whole. Family health conversations via telephone were feasible to both families and registered nurses, although fewer and shorter conversations were preferred by registered nurses. This thesis highlights the divergence between family caregivers’ experiences and needs, and registered nurses’ perceptions about family caregivers’ situation and attitudes toward the importance of family involvement. It adds to the knowledge on the importance to acknowledge family caregivers as a resource and to support and involve them in heart failure nursing care. One feasible and successful way is to conduct Family health conversations via telephone in nurse-led heart failure clinics.

The rapid growth of plastic waste from food packaging around the world demands renewable substitutes, such as natural fibers and biocomposites. Wood fibers are natural fibers extracted from trees and are commonly used in packaging. In order for renewable alternatives to compete against plastics and other non-renewable materials, a better understanding of the mechanical properties of single fibers at the micro-scale are necessary. A great deal of previous research into the mechanical properties of single wood fibers has focused on their tensile behavior, however, little work has been published about their compressive behavior. It is difficult to measure the compressive strength of single fibers directly due to fiber buckling. The purpose of this study is to investigate how post-buckling of single wood pulp fibers affects the mechanical properties of fibers in tension. Two alternative hypotheses were tested through experiments in The Odqvist Laboratory for Experimental Mechanics at KTH. The major part of the thesis process has been invested in developing components called grippers, and testing methods for the Single Fiber Testing System, in order to be able to perform the experiments. The existing grippers were tested and alternative grippers were developed, as well as an alternative testing method without grippers, called the Paper frame method (PFM). PFM was used in the final experimental work to test the hypotheses. The main finding from this study is that there is not enough evidence to suggest that the tensile strength or tensile stiffness of single wood fibers are significantly reduced by post-buckling damage. This finding is mostly relevant in the research and development of fibrous material with larger distances between individual fibers, such as low-density fiber network materials. The main findings from the single fiber testing methods development were that the existing grippers cannot prevent fiber slippage. Furthermore, the alternative gripper 22A with its arc design generates higher grip force than previous grippers but lacks surface friction in the contact region in order to prevent fiber slippage. PFM has an experimental success rate of over 80 % for trained users and easy usage for the operator. The testing equipment Single Fiber Testing System displays several systematic errors occurring in the post-processing process of tests with cyclic loads. / Den snabba tillväxten av plastavfall från livsmedelsförpackningar runt om i världen kräver förnybara alternativ, såsom förpackningar gjorda av naturfibrer och biokompositer. Träfibrer är naturliga fibrer som utvinns från trä och används ofta i förpackningar. För att dessa förnybara alternativ ska kunna konkurrera mot plast och andra icke-förnybara material krävs en bättre förståelse av de mekaniska egenskaperna hos enskilda fibrer på mikronivå. Det finns en omfattande forskning om de mekaniska egenskaperna i drag hos enskilda träfibrer. Däremot existerar det lite publicerad forskning om träfibrers kompressionsegenskaper. Kompressionsegenskaperna är svåra att mäta direkt på grund av fiberknäckning. Syftet med denna studie är att undersöka hur skadan som uppstår efter knäckning av enskilda träfibrer påverkar de mekaniska egenskaperna hos fibrer i drag. Två alternativa hypoteser testades genom experiment i Odqvistlaboratoriet för experimentell mekanik vid KTH. Huvuddelen av examensarbetet har investerats i att utveckla grepparmar och testmetoder för testmaskinen Single Fiber Testing System, för att kunna utföra experiment. De befintliga grepparmarna testades och nya grepparmar utvecklades, och även en alternativ testmetod utan grepparmar som kallas Paper frame method (PFM) utvecklades. PFM användes i det sista experimentella arbetet för att pröva hypoteserna. Huvudslutsatsen från denna studie är att det inte finns tillräckligt med bevis för att stödja hypotesen att enskilda träfibrers draghållfasthet eller dragstyvhet reduceras av skada som uppstår efter knäckning. Detta resultat är mest relevant för forskning och utveckling av fibernätverks material med större avstånd mellan fibrerna, såsom fibermaterial med låg densitet. Huvudslutsatserna från utvecklingen av testmetoder var att de befintliga grepparmarna inte kunde förhindra fiberglidning. Den alternativa grepparmen 22A med sin bågkonstruktion genererade högre greppkraft än tidigare grepparmar men saknar rätt beläggning i kontaktområdet för att förhindra glidning av fiber. PFM har en hög test framgångsgrad med över 80 % för erfarna användare och den är enkel att arbeta med. Testmaskinen Single Fiber Testing System visar flera systematiska fel som blir märkbar under dataanalys av tester med cykliska belastningar.

Studien tillverkar en modell av en värdeflödesanalys hos ett tillverkningsföretag för att se hur värdeskapande företaget är. Studien tar även fram förbättringsförslag på hur företaget kan bli mer värdeskapandeoch effektiva i sitt arbete.

Detta arbete visualiserar värdeflöde av solceller vid tre olika typer av solcellsinstallationer följt av förslag till förbättring gällande ett växande installationsföretag i Sverige. Genom värdeflödesanalys kan vi se tydliga samband mellan snabb tillväxt och logistiska problem, där spårbarhet, lokaler och personal är viktiga faktorer som behöv bindas samman för att skapa ett så optimalt flöde som möjligt. Resultatet är delade i två grupper. En grupp består av visualisering och information kring hur värdeflödet ser ut och den andra av vilka förbättringsmöjligheter företaget har för sin framtida verksamhet. Vi kan också se att företaget har stor potential att öka sin lönsamhet genom att via affärssystem utveckla sin logistikhantering samt sammankoppla företagets olika instanser för att nå en mer effektiv installationsprocess. / This report visualizes the value stream of solar cells at three different types of installations, followed by proposal of improvement at a growing installation company in Sweden. Through value stream mapping, we see a clear connection between a fast growing rate and logistical problems, where traceability, facilities and staff are key factors, which needs to be connected to create as optimal flow as possible. The results are divided into two groups. The first consists of visualization and information of the current value stream and the second of what kind of improvement we suggest the company takes into consider to go even further. We can also see that the company has great potential to increase its profitability by implementing ERP to its logistical department and to connect the other departments to reach a higher level of efficiency.

Att integrera insamling och analysering av användardata inom produktutveckling förekommer hos företag inom alla branscher över hela världen. Användardata kan ge ett företag information om användare och den informationen kan i sin tur utnyttjas för att utveckla befintliga och nya produkter. Syftet med studien är att undersöka hur användardata och andra arbetssätt i kombination kan identifiera och tillfredsställa kundbehov under utveckling av webbplatser och appar. För att besvara frågeställningen byggdes en teoretisk referensram från en vetenskaplig litteraturstudie. En stor del av litteraturstudien består av Kano modellen för att förklara sambandet mellan olika kundbehov och kundtillfredsställelse. Vidare presenteras vanligt förekommande användardata och andra arbetssätt. Sedan genomfördes en kvalitativstudie hos fyra företag som arbetar med produktutveckling av appar och/eller webbplatser. Den kvalitativa studien bestod av semi-strukturerade intervjuer. Resultaten från den kvalitativa studien analyserades sedan och jämfördes mot den teoretiska referensramen. Efter analys och diskussion av resultaten visar studien att en kombination av användardata och andra arbetssätt är fördelaktigt i en produktutvecklingsprocess för att uppnå hög kundtillfredsställelse. Vidare upptäcker studien svårigheten i att mäta kundtillfredsställelse då användares behov ständigt förändras samt för att tillfredsställelse oftast mäts på specifika produktfunktioner, inte produkten i sin helhet. / Integrating collection and analysis of user data within product development is occurring in companies worldwide and across all industries. User data can provide a company with information about the users which can be utilized to develop existing and new products. This study aims to explore how a combination of user data and other work methods can identify and satisfy customer needs during the development of websites and apps. To answer the research questions a theoretical framework was built from a scientific literature study. The literature study gives much focus to the Kano model to explain the connection between different customer needs and customer satisfaction. Additionally, common user data and other work methods are presented. Subsequently, a qualitative study was conducted at four companies who are working with product development of apps and/or websites. The qualitative study consisted of semi-structured interviews. The results from the qualitative study were analysed and compared to the theoretical framework. After analysis and discussion, the study shows that a combination of user data and other work methods is profitable in a product development process to achieve high customer satisfaction. Furthermore, the study discovers the difficulties in measuring customer satisfaction since customer needs are constantly changing and also because customer satisfaction is often measured on specific product features, not the product as a whole.