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Hinder och möjligheter för elektrifiering av lokal och regional lastbilstrafik
No full textTunga vägtransporter står för en betydande del av transportsektorns totala utsläpp. För att
minska dessa har lastbilstillverkare börjat introducera batterielektriska lastbilar, men
spridningen är fortfarande begränsad. Syftet med studien är att identifiera de huvudsakliga
hindren och möjligheter för åkeriers övergång till elektriska lastbilar, samt att kartlägga
lösningar och nödvändiga förändringar som krävs i åkeriers affärsmodeller för en övergång till
elektriska transporter på lokal och regional nivå. För att besvara forskningsfrågorna
genomfördes kvalitativa semistrukturerade intervjuer med sju åkerier samt representanter från
en lastbilscentral, en speditör och en kommun. Intervjuerna syftade till att få en nyanserad bild
av hindren och möjligheter och resultaten analyserades genom en analytisk generalisering.
Resultaten analyserades i sju huvudområden: kunder, investerings- och driftskostnader, teknisk
prestanda, omvärldsfaktorer, transportrutter, laddning och laddningsinfrastruktur och åkeriers
affärsmodell.
De främsta hindren inkluderar de höga investeringskostnaderna för elektriska lastbilar,
osäkerheter kring restvärden och batteriets livslängd, samt otillräcklig laddningsinfrastruktur.
Affärsmässiga hinder för elektrifieringen karaktäriseras av att åkeribranschen är en
konkurrensutsatt marknad med låga marginaler och korta kontraktstider, vilket gör det svårt att
motivera långsiktiga hållbarhetsinvesteringar. Sammanfattningsvis visar studien att
elektrifiering både är tekniskt och affärsmässigt möjlig, särskilt för distribution i stadsmiljö och
för åkerier som har möjlighet att ladda i egen regi. För att övervinna hindren behövs fortsatt
riktade stöd, ökad kunskap om befintliga incitament och en branschförändring där hållbarhet
värderas högre än kortsiktig kostnadsminimering. Framtida forskning bör fokusera på hur
saminvesteringar mellan åkerier kan koordineras, hur frekvensreglering kan nyttjas som intäkt
för åkerier samt hur nya kontraktsstrukturer kan underlätta omställningen
Intent-Driven Code Generation for Android Application Testing Using Large Language Models
No full textModern Android interfaces evolve rapidly, and conventional UI test automation struggles to keep pace with this change. This thesis presents an intent–driven framework that leverages large language models (LLMs) in combination with multi-modal UI representations to translate natural-language testing goals into executable Android tests. While inspired by crawler-based exploration, the framework adopts a modular architecture that separates planning, selection, execution, and observation stages. It incorporates memory for state tracking and includes an evaluator– optimizer loop to refine LLM outputs dynamically during execution. A hybrid screen representation—combining XML hierarchies and screenshots—enables the system to reason over both structural and visual elements of the UI, while a Python-based control layer drives actions on physical devices.
The framework is evaluated on three production-grade Volvo Group applications (Alarm Clock, System Settings, and Load Indicator). Across 45 reference scenarios, the generated tests achieve a 60% aggregate pass rate – compared to manual tests at 87%, reach up to 88% functional correctness, and reduce the amount of written code by as much as 70% compared to manually implemented baselines. Ablation studies show that visual input in addition to XML consistently supports task success and rarely confuses the model, contributing to improved reasoning across a wide range of UI challenges. XML remains valuable for precise element localization, especially where structural anchors are critical. A reasoning analysis over 42 planner steps yields an average score of 4.3 out of 5 for correctness, indicating strong semantic alignment between global testing goals and selected local actions. The framework exhibits weaknesses in dynamic screens, complex seekbar interactions, and backend-dependent states, where test reliability remains limited.
This work contributes a modular LLM-based system for intent-driven UI testing, empirical evidence of its effectiveness and conciseness on industrial applications without model fine-tuning, and practical design guidelines for future intelligent testing tools, including prompt structures, tool invocation patterns, and memory-based tracking heuristics.
Overall, the study shows that combining multi-modal LLM reasoning with structured UI representations advances automated mobile testing toward more adaptive, maintainable, and goal-aligned workflows
Alternativa material för ventilationskomponenter
No full textDetta examensarbete utforskar potentialen hos alternativa material för
användning i ventilationskomponenter, med målet att öka medvetenheten och
intresset inom branschen. Genom att belysa innovativa materialval strävar
arbetet efter att inspirera fler aktörer att överväga hållbara och effektiva
alternativ. Detta för att på ett innovativt sätt ta fram förslag till hur dagens
aktörer kan hantera de hårdare lagarna och reglerna gällande klimatpåverkan.
Examensarbetet lyfter flera möjliga material och utforskar dess möjligheter inom
branschen.
Examensarbetet inkluderar även en djupgående analys av materialet kartong.
Genom att konstruera prototyper och utföra tester, utvärderas materialets
prestanda och lämplighet för användning i ventilationssystem. Dessa insikter kan
hjälpa till att bedöma materialets potential som ett alternativ till traditionella
material.
Syftet med detta arbete är att stimulera intresse och diskussion kring nya
materialmöjligheter inom ventilationsbranschen, med förhoppningen att främja
innovation och hållbar utvecklin
Breathing monitoring with RFID sensing: Tag Antenna Design and Signal Processing
No full textReal-time monitoring of respiratory function plays an essential role in both clinical
diagnosis and pulmonary rehabilitation. In this work, we proposed a novel respiratory
monitoring solution based on ultra-high frequency (UHF) radio-frequency
identification (RFID) technology for local measurement of breathing at multiple
locations simultaneously. A respiratory monitoring system was built using commercial
RFID devices, and a signal processing algorithm was developed to extract
respiratory features. The results demonstrate high accuracy in both respiratory
rate and temporal pattern compared with a reference piezoelectric (PZT) respiratory
belt. Moreover, two compact tag antennas were designed and optimized to
operate on the human body. Two different methods, stencil printing and copper tape
engraving, were used for tag antenna fabrication, with advantages and challenges
analyzed. Overall, our study suggests that RFID technology holds a big potential
for non-invasive and localized respiratory monitoring
Graph Neural Networks for Mobile Robots: A Systemic GNN Design Solution for Traffic in AGV Systems
No full textAutomated Guided Vehicle (AGV) systems improve modern warehouse efficiency
but require extensive effort in designing the virtual road networks (also known
as layouts). A key evaluation metric in this process is waiting time. Traditional
simulation-based methods for waiting time estimation are time-consuming, high lighting the need for faster predictive models. In this thesis, we explore Graph
Neural Networks (GNNs) for predicting the waiting time on each road segment. We
propose a hierarchical GNN framework that integrates a classifier to detect con gested segments and a regressor to estimate the waiting time, effectively addressing
the wide-spreading data imbalance issues. Experimental results demonstrate that
the framework captures meaningful patterns, providing a potential alternative to
traditional simulations in layout design
Järnsand som ersättning för kiselsand i fluidiserade bäddpannor för kraftvärmeproduktion
No full textUtveckling av arklamineringsmetod för additiv tillverkning
No full textThis study documents the process of investigating methods for cutting and soldering
TRILLIUM® clad aluminum sheet, with the aim of developing a more cost-effective
method for metal-based additive manufacturing through sheet lamination. The work
is divided into several parts: an introduction to the topic, a theoretical part where
different methods are compared, an experimental part where a selection of these
methods are tested practically, and prototype development phase where selected
methods are applied more directly and implemented. For the cutting, the results
show that cutting with graphite rods is possible but needs to be further developed
or replaced by another approach to achieve reliable and precise results. In case of
joining, soldering with a hot plate under pressure proved to be a working method.
The project proves that there is potential for the development of a more cost-effective
metal-based additive manufacturing method.
Keywords: TRILLIUM®, aluminum, cutting, soldering, additive manufacturing, sheet
lamination, 3D printer, metal-based AM, prototype developmen
Transfer Learning for Battery Health Forecasting: From Lab to Real World Data
No full textAccurately forecasting lithium-ion battery health in electric vehicles remains challenging
due to the scarcity and variability of real-world data and the disconnect
between controlled laboratory tests and in-service operation. To address this, a
transfer-learning framework is proposed, that leverages diverse lab datasets and
small amounts of vehicle-specific data to produce personalized State of Health (SOH)
and Remaining Useful Life (RUL) forecasts. The proposed method employs a dual
LSTM architecture, where one branch ingests historical SOH trajectories, while a
parallel branch processes simple statistical descriptors (mean and standard deviation
of voltage, current, and temperature) per cycle. The outputs of the two LSTMs are
concatenated and passed through a lightweight MLP to yield cycle-wise forecasts.
Models were trained on three open-source lab datasets (MIT, XJTU, HKUST)
encompassing varied chemistries and cycling protocols, then evaluated both on a
held-out lab domain and on real-world EV data from nine vehicles spanning 18–30
months of operation. Results demonstrate that the dual LSTM consistently outperforms
simpler baselines, with fine-tuning on early-life data yielding substantial
accuracy gains. Our framework thus effectively provides a step towards bridging the
lab-to-road gap, enabling scalable, adaptive battery management
Mariestad 2040; Mariestad and the 7 objectives of the municipality’s; detailed comprehensive plan 2040
No full textThe municipality of Mariestad is in its
most transformative phase since the
postwar era. The municipality estimates a
population increase from the current 25
000 to 40 000 inhabitants by 2040 in the
wake of new industrial establishments
and expansion, including the Volvo
Group’s battery cell factory.
In 2024, the municipality adopted the
Detailed Comprehensive Plan 2040
(DCP), providing a strategy for 7200 new
housing units in Mariestad. The DCP
identifies 7 objectives for Mariestad: the
close-knit (nära) town, the living town, the
safe town, the diverse town, the welldesigned
town, the green lakeside town,
and the proud town of the future.
The master’s thesis argues that these 7
objectives are connected to each other,
and strongly influenced by the first
objective, the close-knit town. The DCP,
however, suggests urban expansion with
areas consisting of 50-75% of singlefamily
homes to supply 3000-6000 of the
new housing units. This risks contributing
to urban sprawl, the opposite of the
close-knit town, and thereby
counteracting all 7 objectives.
The design presented in the master’s
thesis aims at shaping an alternative plan
for Mariestad which more closely aligns to
the 7 objectives of the municipality’s
Detailed Comprehensive Plan. The design
distinguishes several centrally located
areas possible areas for new
development for 12 000 new residents
within 2 km of the town center in
Mariestad without exceeding a floor
space index of 1.2. The sites of Yttre
Hamnen, Katthavet, Marieforsleden,
Tidan’s Kvillar, Norra Katrinefors,
Electrolux and Tidan’s Västra Strand are
described in more detail, where the
density of the site and its role in the town
as a whole is explored.
The design unlocks dormant qualities
around the river Tidan and the former
Electrolux factory, connecting the town
over the water and providing pleasant
public space to stimulate urban life, while
also creating new flows through the
historical town center, Gamla Stan, in
order to stimulate urban life. Space syntax
analysis identifies that the design
improves the centrality of Gamla Stan.
The proposed development is on land
currently occupied by open grassland, car
infrastructure or sprawling industries. This
risks causing higher initial investments in
groundwork, relocation of industries and
a decreased car capacity. This is deemed
as reasonable trade-offs to the increase in
qualities of the 7 objectives generated by
the design. By investing in the close-knit
town and the qualities which follow,
Mariestad improves its chances of thriving
independently from the future of the
Volvo battery factory
Marginal abatement cost comparison of climate improvement measures in civil construction; a study of climate improved concrete, asphalt and fuel alternatives
No full textThis study evaluates the cost-effectiveness and feasibility of climate improvement
measures in civil construction by comparing alternative materials and fuels for asphalt,
concrete, and heavy machinery. The research addresses a growing demand
for sustainable infrastructure by analyzing the marginal abatement cost (MAC)
of selected measures to reduce greenhouse gas emissions. Through a combination
of literature review, interviews with industry professionals, and quantitative data
from Skanska’s operations, the study constructs a Marginal Abatement Cost Curve
(MACC) tailored to a hypothetical mid-sized civil project. Key findings highlight
that certain measures, such as using recycled asphalt with bio-based binders and
transitioning to electric machinery, can offer both environmental benefits and economic
advantages. However, barriers such as procurement practices and knowledge
gaps among stakeholders often hinder adoption. The thesis concludes by emphasizing
the importance of integrating environmental and financial assessments into
project planning to support cost-efficient decarbonization strategies in the construction sector