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This report is about a novel approach to attenuation of fan noise in aerial vehicles, by way of implementing a ducted fan in the chassis of a four meter blended wing body plane. Three different one meter PVC pipes were used and their performances as silencers were tested by measuring the sound power level and calculating the insulation loss compared to a fan by itself. The ducts were either empty or lined with acoustic absorbents and micro perforated panels. Experiments were carried out in the reverberation room at KTH Marcus Wallenberg laboratory for sound and vibration research using the guidelines in ISO 3741 (2010). The results showed that the empty duct lead to a 15.3 dB(A) insulation loss with no decrease in thrust from the fan. The absorbent and micro perforated panel, however, lead to a 22.7 dB(A) insulation loss while giving a major decrease in thrust of more than one order of magnitude. The results show the failure of implementation of the latter two silencers due to choking, but also the success of the empty duct. This shows that there is room for improvement and perhaps even a future possibility of a successful implementation in a real vehicle.

This thesis provides insights into the feasibility of managing product requirements in a concept leveraging an object-centric information model. The aim of this concept is to provide efective management of product requirements in the context of rising volume and complexity of requirements. Firstly, benefts and challenges between the current document-centric way of managing requirements and the novel object-centric concept for managing requirements are mapped and presented. Secondly, the organizational prerequisites necessary for adopting the object-centric product requirement applicability concept are explored and insights into how this transition can be facilitated with knowledge management are generated. Thirdly, the accuracy of this novel concept is evaluated in terms of applying the correct requirements onto products and not more nor less. The methods in this thesis are of mixed nature and combine qualitative and quantitative data sets. The quantitative data was collected from the analysis of the requirement applicability concept and the previous tests of the same concept on diferent products at Company X. The analysis of quantitative data for concept accuracy revolved around interpreting the nature of negative- and positive delta values following an automatic application of requirements in the novel object-centric concept. The former of these delta values relates to relevant requirements missing onto products whereas the latter relates to non-relevant requirements being applied following the automatic application. The qualitative data was collected mainly through a comprehensive literature review, semi-structured interviews, a workshop, meetings, Company X documents and observations. The analysis of qualitative data was done via an adaptation of two frameworks: The Multi-Dimensional Framework for Digital Transformation by Hanelt et al, 2021 and The Process of Organizational Knowledge Creation by Nonaka, 1994. These adapted frameworks were leveraged to generate insights into the necessary organizational prerequisites for adopting the object-centric product requirement applicability concept. While benefts and challenges exist between the two diferent ways of managing requirements, these are not weighted and thus no defnitive conclusion on best practice is drawn. Instead these fndings provide organizations a reference point for evaluating each approach in relation to their own circumstances. Some of the prerequisites identifed as critical for adopting an object-centric product requirement applicability model are a digital library of requirement specifcations that are convertible to object-centric data format, and a suitable PLM strategy chosen by the Top Management Teams that is aiding the development of the concept. As for knowledge management in order to transition to the new concept, fndings show that standardized knowledge creation and knowledge exchange is necessary as well as developing centralized knowledge databases. Lastly, the quantitative fndings indicate that the applicability concept is accurate, but that there is a need for additional iterations with model improvements where the negative delta can be eliminated and the positive delta held at an acceptable level. Den här studien ger insikter om genomförbarheten av att hantera produktkrav i ett koncept som utnyttjar en objektcentrerad informationsmodell. Syftet med detta koncept är att tillhandahålla efektiv hantering av produktkrav i samband med att de ökar i volym samt komplexitet. Studien kartlägger först fördelar och utmaningar mellan det nuvarande dokumentcentrerade sättet att hantera krav och det nya objektcentrerade konceptet. Även de organisatoriska förutsättningar som krävs för att införa det objektcentrerade produktkravskonceptet undersöks i samband med hur denna övergång kan underlättas med hjälp av kunskapshantering. Slutligen så utvärderas det objektcentrerade konceptet för kravapplicering beträfande hur exakt konceptet är i att applicera rätt krav på produkter. Metodiken i denna studie kombinerar kvalitativa och kvantitativa datamängder. Den kvantitativa datan samlades in från analys av kravappliceringskonceptet samt de tidigare testerna av konceptet på olika produkter som gjorts av Företag X. Analysen av kvantitativ data för hur exakt konceptet är i att applicera rätt krav kretsar kring att förstå grundorsakerna till de negativa och positiva deltavärden som uppkommit efter en automatisk applicering av krav i det nya objektcentrerade konceptet. Det negativa deltavärdet relaterar till nödvändiga krav som saknas på produkter, medan det positiva deltavärdet avser icke-relevanta krav som har applicerats efter en systemförfrågan och automatisk applicering av krav. Den kvalitativa datan samlades huvudsakligen in genom en omfattande litteraturstudie, semistrukturerade intervjuer, workshops, möten, dokument från Företag X och observationer. Analysen av kvalitativ data gjordes via en anpassning av två vetenskapliga ramverk: The Multi-Dimensional Framework for Digital Transformation av Hanelt et al, 2021 och The Process of Organizational Knowledge Creation av Nonaka, 1994. Dessa anpassade ramverk utnyttjas för att generera insikter i de nödvändiga organisatoriska förutsättningarna som krävs för att införa det objektcentrerade kravappliceringskonceptet i en organisation. Fördelar och utmaningar med de två olika sätten att hantera krav viktades inte i denna studie, därför dras ingen defnitiv slutsats om bästa praxis. Istället ger dessa fynd en referenspunkt till organisationer att utvärdera bästa praxis i förhållande till sina egna omständigheter. Några av förutsättningarna identiferade som kritiska för att tillämpa en objektcentrerad produktkravappliceringsmodell är ett digitalt bibliotek av kravspecifkationer som är konverterbara till objektcentrerat dataformat, samt en PLM-strategi införd av de högsta ledningsgrupperna som hjälper till med stödja det objekcentrerade konceptet för produktkravsapplicering. Vad gäller kunskapshantering för att övergå till det nya konceptet visar resultaten att standardiserad kunskapsskapande och utbyte av kunskap är nödvändigt, samt utvecklingen av centraliserade kunskapsdatabaser. Slutligen indikerar de kvantitativa resultaten att tillämpningskonceptet är noggrant, men att ytterligare iterationer med modellförbättringar behövs där den negativa deltan kan elimineras och där den positiva deltan hålls på en acceptabel nivå.

This thesis report revolved around the cloning process of plasmids. Attempts of cloning the red fluorescent protein mCherry, and the green fluorescent protein EGFP from various plasmids, into other plasmids containing different cell-junction/cytoskeleton plasmids were made. These plasmids were first amplified using PCR, and then cloned using Gibson-Assembly, and then transfected into live HEK293T or MDCK-II cells. After the transfection, the cells were examined in a microscope. The results showed no signal or localization for the cloned plasmids in their respective corresponding channel, 561 nm for the red fluorescent protein mCherry or 488 nm for the green fluorescent protein EGFP. The step that went wrong was the PCR step in the cloning process, since the backbone vector was not successfully amplified. The reasons for this was either that the backbone vector was too long, the primers regions were to rich with Guanine and Cytoseine, or the primers being too long. Den här tesen kretsade kring kloningsprocessen för plasmider. Det gjordes försök att från plasmider klona in det röda fluorescerande proteinet mCherry, samt det gröna fluorescerande proteinet EGFP in i andra plasmider som innehöll olika cell-junction proteiner. Både det fluorescerande fragmenten och plasmid-vektorerna innehållande cell-junction proteinerna amplifierades med PCR. Sedan gjordes Gibson-Assembly som var själva kloningsmetoden. Efter det transfekterades HEK293T, samt MDCK-II celler med lösningen från Gibson-Assembly kloningen. Dessa celler undersöktes sedan i mikroskop. Resultatet visade inga tydliga signaler varken i 561 nm kanalen (mCherry), eller i 488 nm kanalen (EGFP), vilket betyder att kloningen inte fungerade. Steget som gick fel var PCR-steget i själva kloningsprocessen, då plasmid-vektorerna inte amplifierades. Anledningen till detta var antingen att själva plasmid-vektorerna var för långa, primer regionerna hade för mycket Guanin och Cytosin, eller att alla primers själva var för långa.

We present an online API to access a number of Natural Language Processing services developed at KTH. The services work on Swedish text. They include tokenization, part-of-speech tagging, shallow parsing, compound word analysis, word inflection, lemmatization, spelling error detection and correction, grammar checking, and more. The services can be accessed in several ways, including a RESTful interface, direct socket communication, and premade Web forms. The services are open to anyone. The source code is also freely available making it possible to set up another server or run the tools locally. We have also evaluated the performance of several of the services and compared them to other available systems. Both the precision and the recall for the Granska grammar checker are higher than for both Microsoft Word and Google Docs. The evaluation also shows that the recall is greatly improved when combining all the grammar checking services in the API, compared to any one method, and combining services is made easy by the API.

Envisioning an inner-city student housing project, adding life to an office-dominated area, and offering a publicly accessible roof terrace and open landscape park. We are proposing a student housing complex, composed of two 355-metres-long buildings with two and three floor levels, respectively, lifted up on pilotis, with corridor rooms and student apartments accomodating a total of 336 students and thus creating a bustling hub of human interactivity. For the proposal, we claim a large strip of land in the southern part of the property “Kvarteret Garnisonen 3” in Östermalm, Stockholm; the southern-most 15 % of the 84 000-square-metre property, previously used as a launching space for ceremonial marches, but currently used mostly for parking spaces and dog walking. Designing the large-scale structure to house many students, with each contributing to the added life to the space, and encouraging human interactions architecturally, by retaining the accessibility of the ground level by way of pilotis, as well as making the roof terrace open to the public, and offering several alternative routes between the levels of the buildings.

I takt med att tekniken utvecklas gör även underhållsstrategierna det. Trots detta är det många företag som fortfarande använder samma underhållsstrategier som man alltid gjort. Olika underhållsstrategier ser behovet av underhåll på olika sätt, allt från att vänta tills felet uppstår till att förebygga fel genom avancerad dataanalys och det kan därför vara svårt för underhållsorganisationer att välja rätt strategi. Detta arbete undersöker hur ett byte av underhållsstrategi kan påverka effektiviteten av underhållet i en större organisation, med fokus på kostnader, personalresurser och tillgänglighet på utrustning. PostNord har valts som fallstudie. De strategier som jämförs och utvärderas är; avhjälpande underhåll, förebyggande underhåll, tillståndsbaserat underhåll samt prediktivt underhåll. Resultatet påvisar ökad effektivitet för tre av fyra strategier, som också ser till företagets behov. Den efterföljande diskussionen av resultatet visar att det framtida behovet är oklart där främst två faktorer som påverkar; årliga volymminskningar samt morgondagens utdelningsmodell. Slutsatsen blir att det finns två olika rekommendationer beroende på hur det framtida behovet ter sig. Om det är ett fortsatt behov av hög tillgänglighet på maskinerna så rekommenderas en kombination av prediktivt underhåll och förebyggande underhåll på drifttid. Om det framtida behovet däremot påvisar att tillgängligheten inte kommer att påverka beslutet i samma grad rekommenderas en kombination av förebyggande underhåll på drifttid och tillståndsbaserat underhåll där tillståndsmätningar görs mot den data som samlas in idag. I båda rekommendationerna räknas fortfarande avhjälpande underhåll in som strategi för hantering av de akuta stopp som kan uppstå. Att titta på andra maskintyper där det framtida behovet framgår tydligare föreslås som fortsatt arbete. As technology evolves, so do maintenance strategies. Despite this, many companies tend not to change maintenance strategy. Maintenance strategies differ significantly in the way they address the need for maintenance, for some the strategy is to provide maintenance after a fault has occurred while others focus on preventing faults through advanced data analysis. With this diversity in approach, it may be difficult for maintenance organizations to choose the right strategy. This thesis examines how a change of maintenance strategy can affect the efficiency of maintenance in a larger organization, focusing on costs, personal resources and availability of the equipment. As a case study, PostNord has been the selected company for the study. The study compares and evaluates four maintenance strategies; corrective maintenance; preventive maintenance; condition-based maintenance; and predictive maintenance. The results show increased efficiency for three out of four strategies, which also meet the needs of the company. In the discussing the results in the context of PostNord, annual volume reductions and future distribution model, are identified as the two main factors that will affect the future validity and application of results. Subsequently, the conclusion consists of two recommendations depending on distribution model and annual volumes. If there is a continued need for high availability in the machines, then the combination of predictive maintenance and preventative maintenance on operating time is recommended. If the future need does impact on the need of availability, then a combination of preventive maintenance on operating time and condition-based maintenance where measurements are made against the data that are accessible today is recommended. Both recommendations still include corrective maintenance as a strategy for managing the emergency stops that may occur. To focus on machines with a clearer future need are recommended for continued work.

Integration of functional materials and structures on the tips of optical fibers has enabled various applications in micro-optics, such as sensing, imaging, and optical trapping. Direct laser writing is a 3D printing technology that holds promise for fabricating advanced micro-optical structures on fiber tips. To date, material selection has been limited to organic polymer-based photoresists because existing methods for 3D direct laser writing of inorganic materials involve high-temperature processing that is not compatible with optical fibers. However, organic polymers do not feature stability and transparency comparable to those of inorganic glasses. Herein, we demonstrate 3D direct laser writing of inorganic glass with a subwavelength resolution on optical fiber tips. We show two distinct printing modes that enable the printing of solid silica glass structures ("Uniform Mode") and self-organized subwavelength gratings ("Nanograting Mode"), respectively. We illustrate the utility of our approach by printing two functional devices: (1) a refractive index sensor that can measure the indices of binary mixtures of acetone and methanol at near-infrared wavelengths and (2) a compact polarization beam splitter for polarization control and beam steering in an all-in-fiber system. By combining the superior material properties of glass with the plug-and-play nature of optical fibers, this approach enables promising applications in fields such as fiber sensing, optical microelectromechanical systems (MEMS), and quantum photonics.

Syftet med denna studie var att utveckla en biokomposit med både fett-och vattenbarriär. Material med dessa egenskaper innehåller idag ofta PFAS-molekyler (per- och polyfluorerade alkylsubstanser). Det är av stor betydelse att byta ut dessa mot ett biobaserat alternativ då de är giftiga och ackumuleras i naturen. Biokompositen utvecklades genom att kombinera icke-trä pappersmassa (75%) och trä pappersmassa (25%) som matris. Därefter tillsattes olika biobaserade additiv i våtände för att påverka materialets egenskaper. Proverna testades på deras dragstyrka, vattenavvisning och fettavvisning. Den stora utmaningen var att lyckas med fettavisningen. 1% Polysackarid 1 tillsammans med 0.5% sizing komponent var det provet som gav bäst resultat. För att utvärdera denna metod gjordes en jämförelse med ytbehandling. Det gjordes genom att stryka på några av de tidigare använda additiven på ytan av matrisen. Ytbehandlingen visade sig ha en större påverkan på fettavvisningen men med liknande eller sämre påverkan på vattenavvisningen. Nackdelen med denna metod är att den kräver ett flertal extra steg i produktionen. The aim of this thesis work was to develop a pulp-based biocomposite material with good water and grease barrier properties. It is important to achieve such properties to able to replace PFAS (poly- and perfluoroalkyl substances) molecules due to their toxicity and accumulation. Different types of pulp were evaluated as the matrix and the optimal matrix was based on non-wood pulp (75%) with wood pulp 1 (25%). This was also combined with several different additives in the wet-end. The samples were tested for their tensile strength, water resistance and grease resistance. The biggest challenge was to achieve adequate grease resistance. 1% Polysaccharide 1 together with 0.5% sizing agent was one of the better samples. It was clear the additives affected each other when used in combination with each other which indicates that wet end chemistry is complex. For a comparison, some additives were also tested as coatings. This technique resulted in better grease resistance but requires several extra steps in the production.

The process of gentrification may be seen as black and white, as at least some of the academic discourse is centered around how gentrifiers are displacing locals. This paper reveals some insight into how the process of gentrification may be more complex. Gentrification is perceived to have an array of outcomes beyond the displacement of locals. This paper uses a qualitative method, using subjective experiences of gentrification, to renew the discussion on the topic. This was done by performing interviews with locals who live in London. Four interviews were conducted, which was limited yet did provide some perception insight. Two specific boroughs were also chosen, Tower Hamlets and Hammersmith and Fulham. The perception also derives from those who work in the creative industry, which consists of theaters, museums, games, and boutiques. This paper examines how this specific industry feels, positively or more negatively, about changes in their urban environment or to their creative business and how they overall perceive gentrification. The aim of this paper and the interview questions is to find out what is the creative industries' perspective on the gentrification process in London. This research was limited by the amount of interviews that were conducted as only four were performed. Although by analyzing the interviews in this paper, it can be seen that there are mixed responses about how the creative industry perceives gentrification.