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Copy Number Profiling of ctDNA via Shallow WGS in NSCLC - Evaluation of an Integrated Workflow for the Detection of Somatic Alterations
(2026) Miller, Josefin
Non-small cell lung cancer (NSCLC) remains a leading cause of cancer-related mortality worldwide, necessitating robust and minimally invasive methods for longitudinal monitoring of therapeutic response and tumor evolution. Liquid biopsies utilizing cell-free DNA (cfDNA) offer a promising approach, however, capturing somatic copy number alterations (CNAs) from circulating tumor DNA (ctDNA) is highly challenging due to low tumor fractions and signal dilution from healthy background cfDNA. This thesis evaluates and optimizes an integrated workflow for copy number profiling via shallow whole genome sequencing (sWGS) at ultra-low sequencing depths (~0.0044x to 0.01x). The bioinformatic pipelines Ion Reporter, ichorCNA, and WisecondorX were systematically benchmarked using healthy controls, an undiluted A549 cell line positive control, and clinical plasma samples. To increase sensitivity for low-fraction ctDNA signals, a bisection strategy was used to adjust the hidden Markov model (HMM) parameters of an existing clinical Ion Reporter workflow. All three pipelines were evaluated across different bin sizes (0.5 Mb, 1.0 Mb, and 2.0 Mb), with ichorCNA and WisecondorX processed under default configurations. The benchmarking framework revealed distinct architectural trade-offs across the pipelines at this ultra-low depth. While the optimized Ion Reporter workflow acted conservatively to minimize false-positive calls in validation controls, WisecondorX achieved the highest overall call accuracy (Macro F1 = 0.548) on the positive control data, and ichorCNA provided the highest sensitivity in clinical samples at the expense of vulnerability to background technical noise. Ultimately, this study demonstrates that at this ultra-low sequencing depth, pipeline selection should align with the clinical objective: a conservative architecture like Ion Reporter is well-suited to reduce false positives, whereas tools like WisecondorX or ichorCNA are better suited when maximizing the detection of low-amplitude variants is the priority.
Assessment of segment-level vortex-induced vibration response of a deepwater drilling riser using high-fidelity modelling
(2026) Pal-Singh, Vijay
Based on the literature reviewed, few studies have analysed the vortex-induced vibration response of a low-aspect-ratio computational fluid dynamics riser model, and the use of dynamic properties derived from a global riser model appears to be largely unexplored. A realistic deepwater drilling riser with buoyancy modules is modelled in OrcaFlex, an extensively-used offshore industry software, using a wake oscillator model. Separately, a short segment of this riser is modelled in CFD using Star-CCM+ in a two-way fluid-structure interaction setup. The segment’s physical, environmental, and dynamic properties are derived from a selected segment in the full-scale riser model in OrcaFlex. The dynamic current-induced VIV response of the segment is compared between OrcaFlex and Star-CCM+ to determine whether the responses are comparable. It is seen that both models display similar dominant response, dominant lift frequencies, and lock-in behaviour across a range of current velocity cases. The RMS cross-flow displacement and lift coefficient present a similar trend across cases, except in cases with significant changes in top tension, in which the RMS values diverge significantly between the full-scale riser model in OrcaFlex and the riser segment model in Star-CCM+. These results indicate that high-fidelity modelling of short riser segments can reproduce the VIV response metrics of a global wake oscillator riser model under various conditions, except in cases where the top tension is changed significantly and complicates global riser dynamics.
Impact of Electrified Construction Machinery on the Electricity Grid An Analysis of Effects on Distribution Substations in Gothenburg from Charging of Battery-Electric Construction Machines
(2026) Ahagen, Albin
The electrification of construction machinery is an important measure for reducing greenhouse gas emissions, local air pollution, and noise from construction sites. However, replacing diesel-powered machinery with battery-electric alternatives introduces new electricity demand patterns that may affect power demand in local distribution grids, particularly through high-power fast-charging and simultaneous peak loads. This thesis investigates how a fully electrified construction machinery fleet could influence the electricity grid in Gothenburg, with a focus on distribution substations operated by Göteborg Energi Nät AB. The study develops representative charging profiles for different construction site scenarios and combines these with historical substation load data from several urban area types, including industrial, commercial, and residential zones. By comparing charging demand with available substation capacity, the analysis identifies where and under which conditions capacity exceedance may occur. Different charging strategies, including reduced fast-charging power and night charging, are evaluated to assess their potential to mitigate grid impacts. The results indicate that electrified construction sites can create significant additional peak loads, especially when several machines charge simultaneously during working hours. The risk of exceeding available substation capacity varies depending on construction site size, charging strategy, substation rating, and local load characteristics. Industrial and commercial areas generally show different capacity margins compared with residential areas, while seasonal variation further influences the available grid capacity, with winter conditions being particularly critical. Reduced charging power and night charging are shown to lower peak demand and improve compatibility with existing grid capacity. Overall, the thesis demonstrates that the electrification of construction machinery is technically feasible but requires careful coordination between construction planning, charging strategies, and distribution grid capacity. The findings highlight the importance of integrating construction-related charging demand into future grid planning and provide a basis for identifying where mitigation measures or grid reinforcements may be required.
Home Alone: Investigating the one-person household typology
(2026) Eskilsson, Ellinor
The one person household is the most common way to live in Gothenburg today, making up 42% of all homes. This group of dwellers is overlooked, since both the existing housing stock as well as the new production derives from the outdated norm of the nuclear family. Alternative solutions often suggest either co-housing and new ways of residing together or minimum space short term solutions, but the numbers say it all - many urbanites spend parts of their adult lives dwelling alone. This thesis aims to investigate design for the one person household in an urban setting, without assuming that the solitude is unintended. The method has been to map the user group through statistical research, to contemplate how a new user group changes the preconditions of housing design and to understand the social bonds in a building through literary studies and previous case studies. Entering the design process, the site was analysed in regards of history, urban context, character and public space. The result is a suggestion for a housing at the site of Kapellplatsen in central Gothenburg. Discoveries regarding the lone dweller are shown in the organisation of the building and the plan layout, while the preconditions of the site inform the materiality and structure. The relationship between the living situation of the dweller, the private and communal space and the urban situation, and how these are connected to spatial and architectural qualities are the central themes. The discussion will hopefully regard positive and problematic aspects of living alone and how the range of solutions might be broadened. The thesis should inspire further discussion and research of the role of the seemingly overlooked sole dwellers in our cities.
Interactive Architecture- architecture as a living organism or a machine?
(2026) Barbiche, Vivian
This project aims to broaden the knowledge within a specific chosen area in Architecture, namely Responsive and/or Senseable Architecture. The term ”Senseable" comes from resembling how digital technology reacts and behaves sensitivity, as human empathy dominates according to the architect and engineer Carlo Ratti. This topic was specifically chosen because of the limited attention it has been given through the architectural education but yet has provided important and thoughtful ideas regarding the development of architecture. When designing, we often think of architecture as something that is fixed and static in which the users should add value to it and not on the contrary. The ideas of moveable objects or elements seem to be farfetched and sometimes impossible due to the indoctrinated way of imagining architecture. Today, as a result of technology and digitalisation, architects and engineers are discovering new ways of using technology within architecture, as nowadays the existence of finished responsive architectural projects are limited. This thesis aims to discover the possibilities of including senses and synchronisation between individuals and architecture in an urban context. This by putting the human in the centre of architecture. It also aims to discover and understand the interaction between art and technology and how it can be perceived by users. Is responsive architecture more seen as a vivid space or more likely as a robotic space? Does it feel like being inside a living organism or a machine? Considering all the robotic and technical devices that are required for achieving interactive environments. The design project is focused on to be a small scale experimental building located in a crowded and trafficked place, in order to facilitate the investigation of syncing with human activities. The design process will include methods like experimentations with prototyping, site-analysis, materiality, designs and electronics. This thesis is mostly seen as an opportunity to experiment in a different field of architecture and to learn more about what it provides for a future use. To increase the knowledge and to try in different ways of thinking and reflecting in architecture as well as to break the barrier of what is whats is not possible to design in architecture . This, due to responsive architecture is still seen as a limited possibility both in the design process but also in the structural building process.