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Lessons from Using Indicators to Evaluate a Municipal Climate Action Plan: A Case Study of the City of Gothenburg
No full textThis thesis aimed to investigate the monitoring and evaluation processes of the
City of Gothenburg’s ECP, with a particular focus on indicators. Monitoring and
evaluation are processes that often fall short, with common challenges being the
selection of appropriate indicators or a lack of structures to support their use.
The employed methodologies included a literature review, interviews with employees
at the Environmental Administration and a thematic analysis, and an evaluation of
the indicators, the indicator system and the data through the use of two frameworks
and select data quality criteria.
The first main finding concerns the indicators’ limited identification of distributional
effects across space and groups. Second, no unified framework for indicator
development was identified, and it instead relies on a few guiding principles, for
example quantitative measurability and the possibility to follow up indicators over
time. The third finding are the challenges and opportunities of indicator use and
data structures in the evaluation process of the ECP, as a result of operating as a
large organization. Lastly, public participation could be utilized in future iterations
of the ECP to ensure that the indicators align with public concerns and values. To
tackle these issues, recommendations include the adoption of a formalized framework
grounded in the guiding principles, developing a shared data system for better
management and collection of data, and increasing public participation by engaging
in citizen dialogue
Optimization and Increased Value of Solar Panels with Home Battery Systems for Swedish Households
No full textAbstract
This thesis investigates the techno-economic viability of residential photovoltaic (PV) systems with and without battery energy storage under Swedish market conditions. Using MATLAB, a comparative analysis is conducted for four system configurations: 5 kW and 10 kW PV systems, each with and without a 10 kWh lithium-ion battery. The energy production potential is modeled using PVGIS data, while economic metrics, Net Present Value (NPV), Return on Investment (ROI), and payback period are calculated based on current electricity prices, feed-in tariffs, and tax incentives such as Sweden’s “Grön Teknik” deduction. Additionally, the thesis implements and compares two battery control strategies: a rule-based heuristic and a predictive model using price signals to optimize battery dispatch. Results show that PV systems without storage provide the shortest payback and highest NPV, particularly when system size is aligned with household demand. Battery integration improves self-consumption and grid independence but reduces financial performance under current market conditions. Predictive control marginally outperforms rule-based strategies in energy savings but yields limited additional economic benefit. The study concludes that while residential PV is currently a financially sound investment in Sweden, battery adoption remains constrained by cost unless justified by non-monetary benefits or future policy shifts
Impact of Cathode Materials, Thickness, and Charging C-rate on Lithium Deposition in Lithium-Ion Batteries
No full textAbstract
Lithium-ion batteries (LIBs) are widely used in modern energy storage systems due to their high energy density, long cycle life, and fast charging capability. However, lithium plating during high-rate charging remains a critical challenge, leading to capacity degradation, impedance rise, and safety risks such as internal short circuits and thermal runaway.
This thesis investigates how cathode material properties, electrode thickness, and charging protocols collectively influence lithium plating and capacity loss in coin cells paired with lithium metal-based anodes. Three cathode chemistries are examined: NMC811 (Nickel Manganese Cobalt), LFP (Lithium Iron Phosphate), and LFMP (Lithium Manganese Iron Phosphate). Galvanostatic cycling was performed under stepwise increasing C-rates (0.1C, 1C, 2C) to evaluate capacity retention and CE behavior. Electrochemical Impedance Spectroscopy (EIS) was conducted after all cycling was completed, to assess the cumulative development of internal resistance and interfacial degradation. The results show that cathode composition significantly affects interfacial stability. NMC811 exhibits the highest initial capacity but suffers from rapid impedance growth at high rates. LFP shows superior cycling stability and minimal impedance change, while LFMP offers intermediate performance but is sensitive to abrupt fast charging. Thicker electrodes tend to accelerate capacity fade due to transport limitations, whereas thinner ones provide more stable cycling behavior. Moreover, stepwise charging protocols improve efficiency across all systems, particularly mitigating degradation in LFMP cells. Overall, this work provides insights into the interplay between material selection, electrode design, and fast-charging strategies, offering guidance for improving the performance and reliability of lithium-ion batteries in high-rate applications
Förbättring av CI/CT/CD-processer för firmwareutveckling och testning av IoT-sensornoder
No full textI dagens snabbt växande IoT-landskap är effektiv firmwareutveckling och bra distribution avgörande för att upprätthålla produktkvalitet och möta behovet av snabba iterationer. Manuella processer för firmwarehantering leder ofta till ineffektivitet, kvalitetsproblem och ökad risk för fel vid uppdateringar. Detta examensarbete beskriver design och implementation av en automatiserad Continuous Integration (CI), Continuous Testing (CT) och Continuous Deployment (CD) process för firmwareutveckling och testning av IoT-sensornoder hos ZESS AB. Arbetet fokuserar främst på företagets Itirub-plattform, som finns i sex olika hårdvaruvarianter där de olika kommunikationsgränssnitt ethernet+, WiFi och LoRa kombineras med sensorgränssnittet analogt eller digitalt. Den implementerade lösningen ersätter en tidigare manuell bygg-, test- och driftsättningsprocess med en automatiserad pipeline som inkluderar variantspecifik konfigurationshantering, automatiserad byggning, artefakthantering och testautomatisering. Systemet utvecklades med Python som primära programmeringsspråk, Jenkins användes som plattform för testning, testerna är skrivna i språket Robot Framework, Git som versionshanteringssystem och JFrog Artifactory som platform för att lagra artifakter. Detta skapade en sammanhängande CI/CT/CD-pipeline som förbättrar utvecklingseffektiviteten och firmwarekvaliteten. Resultaten visar betydande tidsbesparingar i utvecklingsprocessen genom automatisering, förbättrad spårbarhet genom Git-integration och utökad testtäckning över alla hårdvaruvarianter. Arbetet visar hur rätt automatisering kan transformera utvecklingsprocesser för inbyggda system samtidigt som rigorösa kvalitetsstandarder för industriella IoT-applikationer upprätthålls
Evaluating Smartwatch Detection of Atrial Fibrillation
No full textSmartwatches, such as the Apple Watch, are increasingly used for monitoring and
detecting serious health conditions like atrial fibrillation (AF), a common arrhythmia
with significant health risks. However, to avoid burdening the healthcare sector
with false alarms, their detection algorithms are designed to minimize false positives,
a choice that may compromise their sensitivity to sparse or intermittent AF.
While previous studies have analyzed the specificity of these alerts, the rate of false
negatives remains underreported. This thesis aims to quantify this performance
gap by evaluating the Apple Watch’s photoplethysmography-based irregular-pulse
notification and its rate of false negatives. Using a large clinical ambulatory ECG
dataset, we modeled and simulated long-term AF episode patterns via two distinct
stochastic methods: a two-state discrete-time Markov chain and a continuous-time
alternating bivariate Hawkes process. Analysis of the simulated data revealed that
a significant proportion of individuals, particularly those with low-to-moderate AF
burden (0.5%–5.5%), risk going undetected for extended periods. For example, for
a burden of 0.5%–1.5%, over 20% of cases remained undetected after five years, and
for a burden of 3.5%–4.5%, over 5% remained undetected after five years of monitoring.
The findings, consistent across both modeling approaches, demonstrate that
detection is highly dependent on the temporal pattern of AF episodes and not just
the AF burden. They also suggest that the Apple Watch algorithm has reduced sensitivity
to certain AF episode patterns, and users should be cautious not to interpret
the absence of an alert as confirmation of a normal rhythm
Development of an integrated FEA solution for shipbuilding
No full textThis thesis presents a Python-driven, MSC Apex–integrated software that automates load-application in alignment with rules specified by classification societies.
The software applies bending, shear, torsion, and pressures—directly from spreadsheet inputs to the finite element model. Utilizing an iterative software development process, the solution was systematically built and validated against external benchmarks on oil tanker midship models. The developed software delivers accurate, repeatable results while eliminating manual data transfers and significantly reduce the different interfaces used throughout the finite element analysis. Its modular architecture easily adapts to other vessel types and rule sets and is designed for seamless future integration into Design-For-Compliance (DFC), paving the way for faster, more transparent structural compliance analyses
Installation Effects of Non-Displacement Piles - A study of installation-induced soil displacements from drilled steel tube piles and cast-in-place piles
No full textIn urban geotechnical design, understanding installation effects of pile foundations
is essential, particularly in dense urban areas with challenging soil conditions such
as those found in Gothenburg. This thesis explores the installation effects of two
types of non-displacement piles; drilled steel tube piles and cast-in-place piles. For
drilled steel tube piles, a qualitative interview study was conducted with indus try professionals, supported by numerical simulations in Plaxis 2D to assess the
impact of soil volume loss through excessive washout. For cast-in-place piles, soil
displacements generated by concrete pressure during casting was evaluated using
the analytical cavity expansion method (CEM) and the shallow strain path method
(SSPM), along with numerical modeling. Both linear elastic and plastic (Soft soil)
constitutive models were used and evaluated for each pile type.
Simulations of drilled steel tube piles demonstrated that excessive washout can no tably affect ground settlements. For cast-in-place piles, analytical and numerical
models aligned well for both lateral and vertical deformations, depending on the
chosen method. Simplified pile group simulations further indicated that significant
ground displacements may occur even at considerable distances. Interviews con firmed that excessive washout is a known issue among contractors. Method selection
should be project-specific, as no solution is universally superior. The critical role of
the drill operator in minimizing installation effects was also highlighted. Diverging
views on current contract formulations revealed uncertainty in responsibility alloca tion. Additionally, a tendency to prioritize faster production methods may elevate
the risk of installation effects, which can be mitigated by setting limits on allowable
ground displacements
A Structured Operational Workforce Planning Process Proposal of a Standardized Process for TPL Warehousing
No full textWorkforce planning is a central component in achieving operational efficiency and
flexibility in TPL warehousing. Since labor is the main cost driver in warehouse
operations, it is important that the right number of employees with the right skills
are at the right place at the right time. Therefore, this study aims to develop a
standardized operational workforce planning process by answering and identifying
what workforce planning process steps should be included, which data is required,
and how the process should be performed. This process is tailored specifically to
the characteristics and challenges of TPL warehousing, with a focus on warehouse
floor personnel.
The study was carried out using an abductive research approach and it is a multiple
case study with four cases of varying size, customer base, and management struc-
ture. Data were collected through 12 semi-structured interviews and 5 site visits.
The empirical findings were further analyzed together with the existing literature.
When sufficient empirical findings and theoretical insights had been collected, re-
search questions regarding the proposal of a standardized workforce planning process
were answered.
In the final phase of the study, it was established which process steps, what data is re-
quired, and how the workforce planning process should be carried out. Subsequently,
a proposal for a standardized workforce planning process for TPL warehousing was
presented. The study used artificial intelligence to assist with sentence formulation
Polygonal contact model for magnetic track brake simulations: Utilization of the Polygonal contact model within SIMPACK for simulations of magnetic track brakes
No full textThis thesis examines the applicability of the Polygonal Contact Model (PCM) for
the simulation of contact between the magnetic track brake and the rail. Since
improved braking performance is the key for further optimization of the railway
system while maintaining high safety standards, accurate and efficient contact modeling
approaches are essential. The aim of this study is to evaluate the accuracy of
the Polygonal Contact Model implementation in the software Simpack 2025x.1 for
the magnetic track brake application. Two scenarios are examined in this thesis.
Results of a paraboloid indenter being pressed onto an elastic halfspace are compared
to an analytical solution for this problem. The impact of PCM using elastic
bodies is also studied on this case. This thesis also describes the preprocessing in
Abaqus necessary in order to successfully implement the elastic extension PCM. The
viability of use for the railway application is further judged by simulating a new and
a worn brake shoe being pressed onto a straight rail
Early movers in sustainability How can early adoption of the Taskforce on Nature-related Financial Disclosures increase financial returns for asset managers?
No full textAs environmental risks are at the forefront of financial markets, nature-related dis-
closures have gained momentum. This thesis investigates how early adoption of the
Taskforce on Nature-related Financial Disclosures (TNFD) influences returns for
asset managers. By applying a Difference-in-Differences methodology to matched
samples of early and late adopters within East Capital’s portfolio, the study assesses
short-term financial impacts using rolling average returns and rolling Sharpe ratios.
Early adopters perform poorly in the short run. These results are contextualized
using signaling theory, the Efficient Market Hypothesis, behavioral finance, and the
early-mover advantage literature. The findings suggest that the effectiveness of vol-
untary ESG signals, such as the adoption of TNFD, is shaped by credibility, investor
attention, and market maturity. The thesis contributes to understanding when and
how sustainability disclosures translate into competitive financial outcomes, offering
implications for asset managers navigating ESG integration and strategic position-
ing