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Otakaari 1 grandhall. Photo: Esa Kapila
 

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Recent Submissions

“Please Wait Patiently”: When Bureaucratic Waiting Becomes the Service
(2025-10-24) Kalashnyk, Yevhenii
School of Business | Master's thesis
Waiting for citizenship is not just a delay but an experience influenced by uncertainty and limited information. This thesis examines how Finnish citizenship applicants navigate bureaucratic waiting through qualitative interviews and observations of online communities. It focuses on how individuals manage uncertainty, search for updates, cope with emotional strain, and maintain agency in a high-stakes service context. The study draws on public administration and service research to show how waiting becomes a lived and strategic part of the citizenship process. Five response strategies are identified: Enduring, Connecting, Investigating, Escalating, and Disengaging. These themes reflect how applicants co-create value (and sometimes co-destruction) through peer support and advocacy while also showing the limits of co-creation under extreme power imbalances. The findings revel tensions between consumer behaviour literature, which often assumes short and voluntary waiting, and real-world bureaucratic delays that put people’s lives on hold. This thesis contributes theoretical insights into value co-creation in public services and has practical implications for making bureaucratic waiting more humane. The thesis argues that treating applicants as partners and providing transparency and support can transform waiting from a period of despondency into a more managed service experience.
Electrochemically-assisted aqueous reduction and its application for surface functionalization
(2025) Herrala, Reima
School of Chemical Engineering | Doctoral thesis (article-based) | Defence date: 2025-11-21
Precious metals like gold and platinum have long been in demand for their aesthetic, technological, and economic value. In modern society, these metals can also be applied to prepare functional materials used in advanced technologies such as fuel cells, chemical conversion, sensors, and more. However, their use is limited by high cost combined with environmentally burdensome primary production, which are both linked to their low concentration in ore. Furthermore, ore grades are declining as rich deposits are used up. Therefore, precious metals within secondary resources and as by-products in the processing of more abundant metals are becoming increasingly important alternative sources, yet their recovery is often impeded by low concentration relative to other elements. The focus of this thesis is in combining the selective recovery of gold and platinum with the preparation of functional surfaces to be used in electrocatalysis. Specifically, the research focuses on the development of a novel electrochemical recovery method named electrochemically-assisted aqueous reduction (EAR), which utilizes short cathodic pulses to generate reductants from concentrated metal ions, such as Cu1+ from Cu2+, to enhance recovery. The studied solutions mimic oxidative chloride leach solutions found in hydrometallurgy, where the concentration of precious metals is in ppm range while base metals can be present in some grams per liter. The results are presented in three parts. First, the EAR method is validated for the selective recovery of Au (5 mg L-1) from cupric chloride (20 g L-1) solutions and Pt (10 – 50 mg L-1) from ferric chloride (1 – 10 g L-1) solutions. These two systems are compared, and the key reactions involved in recovery are studied. In the following section, EAR is combined with bio-based carbon fiber electrodes prepared by electrospinning lignin. This approach is used to form functional surfaces to be used in electrocatalysis of ethanol oxidation and CO2 reduction. Increasing the carbonization temperature (700, 900, 1100 °C) is shown to make gold recovered via EAR more evenly distributed on the fibers and improve electrocatalytic activity. Finally, the impact of both electrochemical parameters and solution composition on the efficiency of EAR is investigated. It is shown that optimal pulse time and potential depend on the solution composition, with more oxidative solutions requiring larger pulse amplitudes and leading to lower current efficiencies. Au recovery is achieved with current efficiencies up to 70% from Cu-Cl solutions and up to 25% from multimetal (Cu-Fe-Al-Ni-Zn-Ag-Pd-Pt) solutions. Selectivity for Au over other precious metals is demonstrated, while the EAR of Pt is strongly inhibited by high chloride concentration and competing reactions. Together, the results demonstrate EAR and carbonized lignin substrates as promising approaches for advancing circular economy practices in the material economy. The future scale up and integration will depend on the prevalence of suitable, chloride-based feeds containing gold or platinum. The studied aqueous reduction phenomena can provide valuable insights in the development of such processes.
Geothermal energy piles design, sizing and modelling
(2025) Fadejev, Jevgeni
School of Engineering | Doctoral thesis (article-based) | Defence date: 2025-11-20
This thesis addresses the challenges associated with the design, sizing, and modelling of geothermal energy piles (GEPs), the lack of validated methods for their use as a renewable heating and cooling solution for nearly zero-energy buildings (NZEBs). GEPs provide both load-bearing and ground heat exchange functions, making them well-suited for use with ground source heat pumps (GSHPs). However, their designs have often relied on assumptions originating from borehole heat exchangers (BHEs), which differ considerably from GEPs in geometry, thermal boundary conditions, and placement, as the layout of GEPs is dictated by the building’s foundation plan. This research aimed to develop and validate a modelling method for assessing the performance of GEPs with thermal storage coupled with a detailed whole building simulation model for a parametric study. The method was developed in IDA ICE and validated using COMSOL Multiphysics and realworld measurement data. The research methodology combined a systematic literature review, model development, validation, and demonstration of the modelling method’s performance using an as-built calibrated model with measured performance data from a commercial NZEB in Finland for energy analysis. A parametric study was conducted to support the development of a tabulated GEPs sizing method for early-stage design, considering factors such as heat pump sizing power, pile spacing and depth, soil type, and the presence of a thermal storage. The findings confirmed that conventional BHE-based modelling approaches are unsuitable for GEP systems due to major differences in thermal boundary conditions, particularly the influence of building floor slabs on ground temperature distribution. The validated GEP modelling method, implemented in IDA ICE and verified with COMSOL simulations, accurately captured these effects and showed strong agreement with measured data from a monitored NZEB in Finland. The model calibration procedure revealed unexpected plant operation due to improper control algorithms, highlighting the importance of monitoring and logging systems in buildings with unconventional plant designs to ensure proper operation and maintain long-term efficiency. According to parametric study results, seasonal thermal storage demonstrated notable improvements in energy efficiency and enabled a reduction in required pile length by over 50% in a specific case. A tabulated GEP sizing guide was developed to support early-stage design, enabling engineers to estimate system configurations effectively without relying on complex simulation tools. The method demonstrated in this thesis can be extended to any climate region and building type.
Walks and steams: Artistic approaches to develop more-than-human ritualisation in polycrisis
(2025) Keski-Korsu, Mari
School of Arts, Design and Architecture | Doctoral thesis (article-based) | Defence date: 2025-11-21
This research asks: what are the possibilities of artistic approaches to develop more-than-human ritualisations in polycrisis? It seeks to reimagine and emphasise relations within the more-thanhuman world as a sentient ecology. Artistic, sensory research and walking methodologies are applied to ritualise with intuitive, caring, and empathic acts. The focus is on the changing conditions of palsa mires in the Circumpolar North, north Fennoscandia, the microbes of the permafrost thaw and the means of walking-with them. Thus, the thesis developed and propose more-than-human ritualisation as a part of nature-ecocultures: permeating art, science, technology, geopolitics and (more-than-) human communities as well as raising awareness of engagement within the sentient ecologies and wellbeing in the context of planetary polycrisis change. The theoretical framework as artistic research draws on posthumanist thought of decentring human and on feminist new materialism, especially on transcorporeality. Ritualisation is positioned within more-than-human relations in sentient ecologies, as shared action, and in the polycrisis changes in it. It offers meaning-making in the tensions between sameness and difference, creating a space where meaning is both maintained and transformed. As such, it is investigating and seeding the new ritual practices of the polycrisis. The research includes written publications with artistic components such as walks and a preevaluated artistic component, an exhibition. The first article focuses on intuitive communication between species to propose it as a method to acknowledge more-than-human agency and consciousness as a relation. The second article incorporates sensory research on natureecocultural relationships, notes changes in this sentient ecology in parallel with scientific findings and proposes a method of walking-with. It initiates walking as ritualising to sense the polycrisis and have an embodied multisensory experience in a technology-driven world. The third publication looks at walking-with as a participatory performance and as a ritualisation to encounter with the microbes of the permafrost thaw. The artistic component, in the form of an exhibition, collects actions as proposals, forming an archive of more-than-human ritualising and embedding artistic practice into an existing ritual, namely sauna bathing. The third article and the artistic component synthetise the methods of the other publications.
Dynamic interactions between ultrasound and water-repellent surfaces
(2025) Drago González, Alex
School of Science | Doctoral thesis (article-based) | Defence date: 2025-11-21
Water-repellent surfaces such as superhydrophobic surfaces (SHSs) and slippery liquid-infused porous surfaces (SLIPSs) are widely used in applications requiring liquid manipulation, antifouling, and drag reduction. Despite their promise, their dynamic control remains limited, particularly under submerged or contactless conditions. Meanwhile, ultrasound is a non-invasive tool capable of exerting precise mechanical forces at microsecond and micrometer scales. To address the need for active, reversible, and localized control of wetting behaviour, this thesis investigates the interaction between ultrasound and water-repellent surfaces using acoustic radiation force (ARF). The aim of this Thesis was to explore the interaction between ultrasound and water-repellent surfaces. Specifically, ultrasound-driven methods were developed to control surface wetting states, enable thermal control, and actuate fluid interfaces non-invasively. SHSs were studied for reversible Cassie-Baxter/Wenzel transitions and were used as acoustic switches to shield or transmit energy depending on their wetting state. SLIPSs were used as a platform for ARF-induced droplet manipulation at the air-water interface, enabling contactless control of microlitre-scale fluids. Experimental setups integrated high-speed imaging, Schlieren imaging, hydrophone pressure mapping, thermographic methods, and numerical simulations. The results showed that focused ultrasound can collapse or restore thin layers of air (i.e., plastrons) within 100 μs, switch local acoustic transmission by over 85%, and protect SHSs from thermal damage. SLIPSs enabled precise actuation of droplets (0.2-200 μL) with speeds up to 2.5 mm s-1, overcoming retention forces thanks to the ARF. Additionally, droplet merging, splitting, atomization and micro-object delivery were achieved using the same acoustic setup. The findings in this Thesis demonstrate that ultrasound can serve as a versatile tool to dynamically control wetting, heat, and fluid interfaces. They also lay the foundation for acoustic surface programming in applications such as microfluidics, biomedical devices, and soft robotics.