Publikationer från KTH
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Torque Validation of a Single-Joint Ankle Dynamometer
No full textThis study aims to evaluate the validity and reliability of torque output from a prototyped single-joint ankle dynamometer. A torque validation framework was developed using ground reaction forces (GRFs) recorded by a force plate, and the centre of pressure (CoP) from a pressure insole. Experimental testing was performed with one single test subject, where both plantarflexion and dorsiflexion were assessed when performing isometric and isokinetic trials. The torque was estimated by transforming the GRF vectors measured by a force plate into a local coordinate system fixed on the dynamometer as well as calculating the moment arm between the ankle joint and the CoP. This externally calculated torque was later compared to the torque from the dynamometer’s own load cell. Results showed that the shape of the GRF-based torque was in general alignment with the load cell torque, but with a consistently lower magnitude. Additional analysis using the normal force recorded by the pressure insole to estimate the torque proved to be closer in magnitude to the load cell torque, suggesting potential errors in the transformation or recording of GRFs. This study thus provides a foundation for further refinements of the validation framework as well as highlighting possible improvements for future work.
Standardiserad styvhetsanalys för lastbilschassin
No full textI detta kandidatexamensarbete har en metod utvecklats för att standardisera styvhetsanalyser av lastbilschassin med hjälp av FEM-simuleringar. Målet har varit att möjliggöra jämförelser av chassins strukturella egenskaper på ett reproducerbart sätt, oberoende av lastbilens specifika konfiguration. Metoden bygger på fyra specifika lastfall - vridande last, longitudinell last, topplast och sidolast. Dessa har valts i samråd med Traton Group R\&D. Lastfallen representerar olika mekaniska påverkanstyper och används för att beräkna respektive styvhetsmått. Metoden har tillämpats på tre olika chassikonfigurationer: Väst 4x2, Öst 6x4 och Öst 8x4. Resultaten visar tydliga skillnader i styvhet mellan dessa konfigurationer och bekräftar metodens förmåga att fånga upp variationer i chassigeometri. En djupare analys av lastfallet topplast visar dessutom hur en förenklad analytisk modell kan ge rimliga uppskattningar av styvheten, vilket öppnar för möjligheten att garantera att metoden används på ett korrekt sätt samt garantera resultatets pålitlighet. Slutsatsen är att den föreslagna modellen är praktiskt användbar och kan utgöra grund för vidareutveckling mot en bredare katalogisering av chassins styvhetsegenskaper. Dock rekommenderas ytterligare validering med fler lastbilstyper samt fortsatt utveckling av analytiska stödfunktioner
Floating Additions Along The Inner-City Quays Of Stockholm : A design proposal for a floating cultural building at Söder Mälarstrand, Stockholm.
No full textUrban förtätning och behovet av nya attraktiva miljöer i innerstäder ställer nya krav på stadsutvecklingen. Söder Mälarstrand i Stockholm har med tiden blivit en plats som idag till stor del fungerar som en transportsträcka, vilket lett till att ett av Stockholms längsta stråk i vattennära miljö idag är outnyttjat. Under de senaste åren har direktiv och strategier tagits fram från Stockholm stad för att aktivera vattennära platser i staden, inklusive Söder Mälarstrand.Detta arbete grundar sig i litteraturstudie, platsanalys och intervjuer som se-dan syftar till ett gestaltningsförslag på hur en flytande byggnad kan bidra till en mer resilient stadsutveckling, samt stöd-ja Stockholms stads ambition att aktivera och tillgängliggöra stadens kajer. Förslaget kommer dels baseras på liknande idéer och projekt från runt om i världen där vattennära byggnader har kunnat skapa värdefulla offentliga ytor i en alltmer trängd innerstadskärna.Förslaget Mälarverket visar att en flytan-de kulturbyggnad kan vara ett alternativ för hur man kan återaktivera kajstråket längs Söder Mälarstrand. Förslaget bidrar till att tillgängliggöra allmänhetens närhet till vattennära miljöer och skapa en mö-tesplats för diversitet och kulturfrämjande.Urban densification and the need for new attractive environments in city centers place new demands on urban develop-ment. Söder Mälarstrand in Stockholm has, over time, become a space that today largely functions as a transit corridor, re-sulting in one of Stockholm’s longest wa-terfront promenades being underutilized. In recent years, the City of Stockholm has developed directives and strategies to ac-tivate and improve access to its waterfront areas, including Söder Mälarstrand.This project is based on literature review, site analysis, and interviews, and aims to present a design proposal for how a floa-ting building can contribute to more re-silient urban development. The proposal draws inspiration from similar ideas and international projects where waterfront architecture has created valuable public spaces in increasingly dense urban cores.The proposal, Mälarverket, demonstrates that a floating cultural building can serve as an alternative approach to reactivate the waterfront at Söder Mälarstrand. The design aims to improve public access to water, and create an inclusive gathering place that promotes diversity and cultural engagement
Inverse Design of an Intermediate Compressor Duct
No full textThe report at hand investigates the concept of a partially physics driven inversedesign method. Starting point is a literature review as an introduction into thecore concepts in fluid mechanics and optimization theory used to develop thetools used in the inverse design algorithm. The algorithm itself consists of twomain parts: A metaheuristic algorithm which is aimed to generate a targetpressure distribution (TPD), as well as a Modified Garabedian-McFadden(MGM) algorithm to create the respective geometry, that resembles the targetpressure distribution. While this two–step process should be applicable to mostinternal flow cases, this study aims to establish and validate it in the context ofaggressive inter compressor ducts. Furthermore, the influence of turbulencemodels in the generation of the wall pressure distributions is investigated. Inparticular, the Standard k-ω and Standard k-ϵ model’s behavior is beingcompared, when facing different levels of aggressiveness. To further developthe established concept, a more advanced process in the TPD generation isexamined: Including an analysis of the impact of the viscous forces and thenature of the model governing equation, qualitatively commenting on its scope.With the current implementation, the in-house inverse solver requiresapproximately 100 iterations of a 3D k-ε solver with standard wall functions—each taking 25 to 30 seconds—to reach a pressure residual level under oraround 1%. With minor modifications to the model’s governing equations thecurrent 2D inverse design algorithm (IDA) framework shows potential forextension to three-dimensional problems
Betygsresultat i den svenska gymnasieskolan: en regressionsanalys
No full textDenna studie undersöker vilka faktorer som påverkar svenska gymnasieelevers resultat på nationella prov. Med statistiskt material från Skolverket genomfördes multipel linjär regressionsanalys, där variabler såsom kommun, skolhuvudman och elevsammansättning (andel kvinnor, andel elever med utländsk bakgrund och andel elever med högutbildade föräldrar) inkluderades. Arbetet innehåller även en grundlig introduktion till regressionsteori. Efter variabelurval, behandling av avvikande observationer och test av variabeltransformation analyserades den slutliga modellen. Resultatet visar att elevsammansättning, elevantal, andel behöriga lärare, skolhuvudman och programtyp har statistiskt signifikant effekt på provresultat. Den slutliga modellens justerade förklaringsgrad R² = 0.59 bedömdes som hög för en samhällsorienterad studie. Arbetet understryker vikten av att kvantitativt analysera strukturella skillnader för att främja likvärdighet i skolsystemet
Equivariant Matrix Factorizations of Symmetric Polynomials
No full textThe action of a finite group on a module over a graded polynomial ring extends to its free resolution, and this extension generalises to modules over hypersurface rings if the polynomial ideal is closed under the group action. We show how the equivariant structure transfers to matrix factorizations when the polynomial itself is -invariant, and study the representations of these factorizations for the symmetric group. We show that the representations in -equivariant factorizations from finite length modules have identical decompositions into irreducible representations, and provide explicit formulas for decompositions in factorizations of from the fat point modules when 0 < a < \deg f
Detection of Personal Data in Unstructured Text Using Deep Learning Models
No full textThis thesis explores the detection of personal data in unstructured text using compact deep learning models for Named Entity Recognition (NER). It evaluates the performance of various deep-learning models, including a bidirectional LSTM and multiple versions of BERT, both with and without a Conditional Random Field (CRF) tag decoder. The primary goals are to evaluate these models based on F1-score, precision, recall, and inference speed, and to compare their effectiveness against an existing rule-based algorithm employed by the software company Northern Parklife AB. We find that these models significantly outperform the traditional rule-based approach on our synthetic dataset. Although there are concerns related to generalizability to real-world data, we conclude that integrating deep learning methodologies, possibly by augmenting existing rule-based systems with a compact model as a secondary validation layer, could potentially improve the sensitive personal data detection processes for organizations like Northern.
Fiction to Form: Architectural adaptation of the Legend trilogy
No full textThis project explores how architecture responds to collapse - environmental, politicaL, and spatial. Set in a future version of Stockholm, reshaped by a 25 meter sea level rise and authoritarian governance, the work investigates how the city fragments and reorganizes through architecture, infrastructure and control.The project began with the dystopian world of the Legend trilogy and evolved into a speculative system, a method for applying principles of elevation, access and governance to any city. Stockholm became a case study, reinterpreted through sectors, typologies and urban thresholds.Using tools such as physical modeling, urban mapping, cinematic storytelling and AI generated imagery, the project tests how architecture can become not just a response to crisis, but an instrument of power, division and adaptation. The result is a city that is both familiar and transformed, still standing, but no longer whole
Vasaskrapan
No full textThis project explores the potential of creating a vertical city center in a highly central location in Stockholm – Odenplan. The existing site is currently planned for demolition and reconstruction as a generic office building. I instead proposed a bold, slender high-rise that introduces flexibility, mixed-use programming, and a strong public presence in the city skyline. The building includes a diverse mix of functions: retail and public services at the base, healthcare facilities (retaining current use), a gym, office floors, and residential apartments on the upper levels – all topped with a public rooftop bar. A key feature is the column grid structure which allows for completely non-load-bearing interior walls, enabling floorplans to adapt over time as urban needs evolve. The concept focuses on densification without sacrificing urban quality. It’s a response to the growing need for multifunctional and sustainable city centers. Rather than designing just a building, I aimed to create a vertical neighborhood – a new landmark that gives something back to the city and offers a more generous and long-term alternative to single-use development
Functional diversities as principle for architectural design
No full textThis project proposes an alternative to the city’s redevelopment plans for Henriksberg, where large-scale housing is set to replace the area’s existing industrial and creative landscape. Instead, I suggest reactivating one of the vacant buildings as a daily activity center (Daglig Verksamhet) for individuals within the LSS system — integrating social care, craftsmanship, and community in a space designed for meaningful interaction. The design is based on eight years of professional experience within LSS, drawing on recurring needs, behaviors, and character traits I have encountered with individuals I have worked with. Rather than treating accessibility as a technical add-on, the project explores how architecture can respond holistically to support independence, orientation, and participation. The proposal strengthens Henriksberg’s existing identity by encouraging collaboration between the daily activity center and the local creative businesses, positioning social care as a shared resource rather than an isolated function. The building is designed to open toward the adjacent 4H farm, creating visual and programmatic connections that invite outdoor activities such as gardening and animal care, a key elements in many activity centers day programs. In short, this counterproposal argues for a socially sustainable, small-scale intervention that builds on Henriksberg’s unique character, offering an alternative narrative to demolition and densification