[dipl] Insinööritieteiden korkeakoulu / ENG

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  • International Benchmarking and Performance Comparison of Tree Species Classification Algorithms using Multispectral Laser Scanning Data
    (2025-02-24) Salolahti, Klaara
     School of Engineering | Master's thesis
    Tree species classification provides important data for forest management and biodiversity mapping. Aspen is among the most important species for biodiversity and associated flora in Finland. While terrestrial and mobile laser scanning show promising results in tree classification, airborne laser scanning is more efficient for larger areas. Incorporating additional features alongside point cloud geometry, such as spectral features, could be valuable in classification. While multispectral airborne laser scanning has advanced, identifying rare species remains challenging, particularly in distinguishing deciduous species. Further research on multispectral airborne laser scanning for tree species classification is needed, especially utilizing high-density point cloud data. The development of deep learning classification methods is a promising field but requires large training datasets. This thesis compares the classification results achieved for 9 species with over 6000 trees, for multiple machine and deep learning methods crafted by the international scientific community. Two multispectral point cloud datasets with different densities were obtained, segmented, and shared with participants. This thesis also aims to observe the differences in classification based on segmentation quality. This thesis found that with the high-density data, deep learning methods achieved the best classification results in all metrics. Machine learning and deep learning methods using the sparser dataset achieved consistent results, displaying their robust ability. Segments that were overlapping with other trees or nearby large trees reached lower recall values than trees that were isolated. The highest overall accuracy value was 87,9% and was reached by a point-based deep learning model.
  • Betonilattioiden liikuntasaumat: Kohti yleistä suunnitteluohjetta
    (2025-02-24) Takanen, Markus
     School of Engineering | Master's thesis
    Concrete expands and contracts due to various environmental factors, such as changes in temperature and humidity. These fluctuations can cause stresses and cracks in the absence of movement joints. Movement joints are essential for ensuring the durability of structures, but in Finland, there is currently no general design guideline for their dimensioning. The objective of this master's thesis is to study movement joints in concrete floors, particularly solutions implemented with bar and plate dowels, and their impact on the capacity and durability of floor structures. The study examines the capacity of movement joints through literature review, manufacturer-provided table values, and load tests, aiming to develop a unified testing method for verifying joint structures. The research explores factors influencing the design of movement joints, such as joint spacing, concrete properties, and loads. A key focus of the thesis is comparing the capacities of different movement joint devices and their suitability for various applications. The results of the load tests indicate that the load transfer capacity of movement joint devices is significantly influenced by both the structure of the joint device and the quality of the surrounding concrete. The load test results provided by participating companies also reveal notable discrepancies between the table values of movement joint devices and the results obtained from calculation formulas. Consequently, when drafting a design guideline, it is essential to consider the differences between actual capacities and existing calculation methods. Based on these differences, the most suitable testing approach for potential further research can also be analyzed. Due to the possibility of further studies, this thesis is limited to unreinforced concrete slabs, meaning that the effects of slab reinforcement and different types of concrete mixes on the performance of movement joint devices were not comprehensively examined. Additionally, the study focuses on heavily loaded industrial floors, so the results cannot be directly generalized to more lightly loaded environments, such as residential or office buildings. These limitations provide a foundation for future research, which could delve deeper into these aspects.
  • Cost Assessment of Offshore Wind in the Baltic Sea
    (2024-12-20) Hietanen, Sara
     School of Engineering | Master's thesis
    As the world shifts towards more sustainable energy solutions, offshore wind power has gained prominence due to its potential and reduced environmental impact compared to fossil fuels. With rising energy demands and the urgent need to cut carbon emissions, offshore wind farms have become essential to global energy strategies, offering the advantage of higher and more consistent wind speeds compared to onshore sites. This study aims to assess the potential costs of offshore wind power in the Baltic Sea by comparing it to the North Sea region. The thesis examines wind conditions, seabed characteristics, logistical challenges, and economic aspects to evaluate the feasibility and future prospects of offshore wind power in the Baltic Sea. The results show that the Baltic Sea has significant potential for offshore wind power development, but region-specific challenges, such as seabed type, shallow water depths, and ice formation, require special attention and solutions. The largest individual cost factors, besides the turbines, are their foundations and installation costs. Furthermore, significant uncertainty and variation were identified in estimating capital costs for projects, depending on the baseline data and the specifications of the modelled offshore wind farm. The gap between the highest and lowest capital cost estimates can reach up to 122%.
  • Assessment of end-life revaluation options for unidirectional carbon fibre rein-forced polymer in circular economy
    (2025-01-27) Moradichargari, Amirali
     School of Engineering | Master's thesis
    Carbon fibres (CFs) are increasingly used in manufacturing of structural systems because of their special characteristics such as being lightweight, corrosion-re-sistant and high-strength. However, this increased amount of CF poses a threat on the environment as CF manufacturing is a very energy-intensive process and the majority of CFs go to landfill after their decomposition causing a relevant CO2 emission and loss of valuable material. This study investigates the possible solutions for the end of life (EOL) of Carbon Fibre Reinforced Polymer (CFRP) rope system and their environmental and economic incentives and their availability as an industrial scale solution. The total CO2 emission and cost of CFRP rope from manufacturing, waste treatment and the outcome of recovery methods (cradle to cradle) were estimated and compared. Landfill, incineration, and co-incineration have been identified as non-recovery EOL pathways, while pyrolysis, fluidized bed, advanced mechanical, and traditional mechanical recycling have been found viable recycling solutions at industrial scale. Moreover, refuse, repair, and reuse have been studied as methods of circular economy to prevent/postpone decommissioning and hence the use of new raw materials. Pyrolysis, and fluidized bed were shown as methods that has the highest potential of CO2 savings and preserving the quality and value of recycled carbon fibre (RCF) while landfill and incinerations are the least favorable methods both from economic and environmental perspectives. Refuse, repair and reuse are methods with the least cost and capital needed and have the potential to compete the recycling methods, but they are not readily available as a solution.
  • The Impact of Regional Development Level on Housing Prices
    (2025-02-16) Kiltilä, Riku
     School of Engineering | Master's thesis
    Historically, urban areas have been expanded by urban sprawl, resulting in low-density, auto dependent cities worldwide. However, current urban planning relies more on smart growth strategies, such as infill development, focusing on a more efficient use of land in urban areas. Although the price impact of infill development has been widely studied, prior research has not examined the relationship between the level of development of the area and apartment prices. Additionally, there appears to be a limited number of studies investigating the price impact of individual construction sites on surrounding apartments. This thesis aims to fill these research gaps by assessing the impact of the level of regional infill development on housing prices in two case areas in Helsinki, Finland by focusing exclusively on non-subsidized multistorey apartment buildings. This thesis consists of a literature review and an empirical analysis. The literature review provides the theoretical framework for the empirical part of the study. First, it describes the institutional background in Helsinki. Subsequently, it assesses existing literature on the principles of apartment pricing, the theory of externalities, and infill development as well as its implications for surrounding properties. Previous studies suggest that infill development may positively affect apartment prices, but the effects are highly context dependent and do not appear to produce long-term price trend changes in the areas of infill. The empirical part of the thesis assesses the development of Kalasatama and Jätkäsaari regions, both of which are newly developed city districts near Helsinki Central Business District. A multivariate regression analysis is used to assess the relationship between the level of development and apartment prices in these case-areas. The results indicate that there may be a slight positive relationship between apartment prices and the development rate of a newly built city region, ranging from 4.4% to 8.4% depending on the used regression model. However, as the results are correlational and partly lack of statistical significance, they should be only considered as indicative evidence of the positive relationship. A secondary objective of this thesis is to examine individual construction sites and determine whether the negative externalities caused by them have a statistically significant impact on local housing prices. Investigating this phenomenon proved challenging, as the sample size decreased extremely small, consisting only of 446 observations from five different blocks. The results suggest that the negative externalities of construction sites may temporarily lower housing prices in the area. However, deficiencies in the dataset led to statistical insignificance of the findings.
  • Generative System Design in Car Powertrain Architecture Optimization
    (2025-01-29) Zafiris, Stefanos
     School of Engineering | Master's thesis
    This thesis proposes the integration of Generative Design and Computational Design Synthesis into a novel framework called Generative System Design, which tries to automate and optimize complex early stage engineering processes in computational engineering design. Generative Design focuses on creating diverse range of design alternatives, while Computational Design Synthesis focuses on optimizing system architectures. However, neither method alone addresses the various challenges of comprehensive engineering projects. Generative System Design aims to narrow this gap by combining the strengths of both approaches, facilitating creation of low-fidelity solutions that can be refined into high-fidelity models by human lead engineering teams. As Generative System Design is still in its early days the research part focuses more on Computational Design Synthesis. The research comprises of two studies. The first study uses the Tower of Hanoi problem as a toy problem to compare three algorithms: Genetic Algorithm, Nested Genetic Algorithm and Simulated Annealing. The results showed that the Nested Genetic Algorithm performed the best in simpler solution spaces, while the standard Genetic Algorithm performed the best in larger more complex solution spaces, which is why it was chosen for the second study. The second study investigates component selection algorithms in car powertrain architecture optimization. The objective was to determine if a modified Genetic Algorithm or a modified NSGA-II could outperform pure random selection. The study revealed that the modified Genetic Algorithm did not provide significant improvements over pure random selection, whereas the modified NSGA-II demonstrated superior results, especially in more complex solution spaces. These studies show both the possibilities and limitations of the algorithms used. Genetic Algorithm showed promise but required a lot of adaptation to constraints which will limit their use in highly constrained scenarios. Algorithms with more flexibility like Reinforcement Learning could offer better performance in more complex problems. The results contribute to the development of Generative System Design and its application to real-world engineering problems.
  • Implementation of a techno-economical calculation model to support SMR business scenario analyses
    (2025-02-14) Kankkunen, Niklas
     School of Engineering | Master's thesis
    The ambitious climate targets established to combat climate change have driven the energy sector, including the heating sector, toward innovative and sustainable solutions. Decarbonizing district heating (DH)—a critical component of urban energy infrastructure that has traditionally relied on fossil fuels—is essential for achieving these targets. In this context, nuclear energy, particularly Small Modular Reactors (SMRs), has emerged as a promising technology. SMRs offer several advantages over traditional nuclear power plants, including smaller size, modular construction, and enhanced safety features, making them well-suited for localized heat production. This thesis focuses on developing and implementing a techno-economic calculation model to evaluate the feasibility and benefits of integrating SMRs, specifically the Finnish-designed LDR-50, into district heating networks. Using this model, various scenarios were simulated and analysed for the Helsinki district heating grid for the year 2030 and compared against each other. In addition to DH model simulations, economic analyses were conducted for the LDR-50, calculating the levelized cost of heat (LCOH) for different numbers of LDR-50 units installed in the network. The estimated LCOH ranged from 23.9 €/MWh to 37.4 €/MWh, demonstrating the economic viability of SMR deployment. The results further indicate that, in addition to being cost-competitive and economically feasible, integrating SMRs into district heating networks would result in significant CO₂ reductions compared to the base case. These findings highlight the potential of SMRs as a sustainable solution for decarbonizing urban heating systems.
  • Työvaihesuunnittelun prosessin kehittäminen ratasuunnitelmavaiheessa
    (2025-02-23) Ala-Ketola, Sofia
     School of Engineering | Master's thesis
    Phasing the construction of a railway is a rarely researched topic in Finland and in the world in general. However, work phase planning is done as part of practical planning. The need for this thesis came about because of the lack of current guidelines regarding work phase planning in Finland. In this thesis, the current state of work phase planning and its possible development directions were studied. The methods included analyzing planning documents as well as expert interviews. The study was conducted as a qualitative study, where the chosen analysis method was content analysis grounded in the study material. The study material was also quantified. The research questions were aimed at discovering, what kind of work phase planning process would be suitable in the railway plan stage in Finland and how the planning documents would best serve the next planning stage as well as capacity planning. The study shows that the interviewees were mostly satisfied with the current format of planning documents. From the point of view of construction stage, the documents should also include the assumptions and constraints used in the plan. Additionally, from the point of view of the capacity planning, it would be beneficial to have the traffic impacts in a table format. Also, the temporary capacity restrictions should be planned with more detail. This is something that also the future EU legislation calls for. The thesis also revealed development directions for stakeholder cooperation. As part of the thesis, a stakeholder analysis was conducted based on the empirical results, literature and the expertise of the thesis author. The construction phase project managers and capacity experts from the Finnish Transport Infrastructure Agency, municipalities as well as capacity planners from Fintraffic were recognized as the most important stakeholders. Additionally, it was revealed that the work phase planning should include more guidance on how to plan from the point of view of safety and environmental aspects, such as environmental permits.
  • Towards Digital Water Resources Governance - The role of digitalization in water resources sector in Finland
    (2025-02-24) Harri, Sofia
     School of Engineering | Master's thesis
    Digitalization is expected to address many pressing challenges in the water resources field including climate change, pollution, and overexploitation. However, limited research has been conducted on the actual role of digitalization and its possibilities and threats in relation to water resources management and governance. The aim of this thesis was to explore the state of digitalization in the water field through the following research questions: 1) How is digitalization understood in the water field, 2) How are the positive and negative effects of digitalization considered, and 3) How should digitalization be developed in the water resources field. The research methods included a literature review, interviews with three water field professionals, and a policy analysis of digitalization and water resource policies. Possibilities and threats of digitalization were identified through the interviews and categorized. The findings indicate that digitalization lacks a universally accepted definition. The term is interpreted differently by individuals and is used rather inconsistently in literature and policy documents. Therefore, it is essential to clearly define digitalization to ensure a shared understanding of its desired outcomes. Developing a definition suitable for water field should also be considered. Based on the interview results, the key possibilities of digitalization included data gathering, technological methods, availability, and efficiency. The key threats of digitalization, based on the interviews, were security, accessibility, data accuracy, usability, and continuity. Comparing these results to the key possibilities and threats found from the literature, the major differences were that sustainability as a threat was emphasized more in the literature while interviewees emphasised more also data gathering and technological methods as possibilities and data accuracy and continuity as potential threats. Digitalization should be developed considering both the possibilities and threats, that the development is intentional towards a desired direction but also considers the threats. Further research is needed to understand digitalization’s affects in the water sector context comprehensively.
  • Aurinkosähköjärjestelmien taloudellinen kannattavuus suomalaisissa kotitalouksissa
    (2025-02-11) Telsavaara, Tuomas
     School of Engineering | Master's thesis
    Small-scale residential photovoltaic power generation have become increasingly popular in Finland in recent years. So-called photovoltaic package solutions have been established by many Finnish electricity companies, and they are marketed, among other things, for the economic benefits they can provide. The aim of this work is to study the economic feasibility of photovoltaic power systems in Finnish households, and the study consists of a literature review and a financial calculation. The literature review examines the technical operating principle of solar panels and photovoltaic systems, and explores major features of photovoltaic systems from the perspective of Finnish laws, regulations and environment. The aim of the literature review is also to determine the key factors affecting the economic feasibility of residential photovoltaic systems. The financial calculation is performed using a spreadsheet program, and it is conducted for three fictitious Finnish detached houses equipped with residential solar power. The first household is a detached house in Rovaniemi with low consumption and self-consumption rate, with a small but still oversized rooftop photovoltaic system with respect to the low electricity consumption. The second household is a detached house in Imatra, heated by air source heat pumps, with a self-consumption rate of approximately 50% and an annual electricity consumption of approximately 19 000 kWh, and 6,2 kWp installed solar power. The third household has an annual electricity consumption of 30,000 kWh and a self-consumption rate of 92%. The household is in Kirkkonummi and is equipped with an 8,2 kWp photovoltaic system. The second and the third household proved to be economically feasibility by the financial calculation. The internal rate of return for the first household is -5 % and the net present value is -2627 euros. The corresponding figures for the second household are 6 % and 935 euros, and the figures for the third household are 17 % and 9839 euros. Based on the results, in addition to the initial investment, the market price of electricity and the discount rate have the most significant impact on economic feasibility. The results also suggest that the self-consumption rate has a significant impact on economic profitability. In addition, the impact of energy fee for electricity transmission seems to be particularly emphasized in locations with a high self-consumption rate.
  • Influent fractionation for Viikinmäki wastewater treatment plant
    (2025-02-24) Petäjä, Eero
     School of Engineering | Master's thesis
    The study conducted in the thesis was to find information on wastewater characteristics in Viikinmäki wastewater treatment plant, including chemical oxygen demand fractions and suspended solids characterization, as well as the daily dynamics of the characteristics. This information is vital for wastewater treatment plant models, as the characterization represents the most calibration work during a wastewater treatment plant model calibration. The chemical oxygen demand fractionation was conducted using physical filtration, chemical flocculation, as well as chemical and biological oxygen demand measurements. Suspended solids were characterized by their concentration and organic nature. Diurnal variation was found in the chemical oxygen demand fractions and suspended solids characteristics. The chemical oxygen demand fractions for the wastewater were determined for a warm time period. Because the thesis was a part of the DIGICARBA-project, that aims to produce a digital twin of the Viikinmäki wastewater treatment plant, continuously measured variables were inspected to find correlation that could be used to estimate the fractions continuously. With both, chemical oxygen demand and suspended solids, moderate negative correlations with influent flow rate and a little higher correlations with influent tunnel water surface level in Viikinmäki wastewater treatment plant were found.
  • Impacts of an Electricity Interconnector between Iceland and UK
    (2025-02-14) Lehtovirta, Lotta
     School of Engineering | Master's thesis
    The aim of this thesis is to assess the impacts of an electricity interconnector between Iceland and the United Kingdom. The study goes through the electricity market liberalisation process in the Europe and the European Union electricity market policies to provide a background for why the United Kingdom and Icelandic electricity markets look like what they are currently. Given Iceland’s electricity system is isolated from other European markets and the United Kingdom’s transitioning electricity market, these two systems provide the basis for evaluating the impact of a potential electricity interconnector. Interconnectors are valuable additions in electricity markets allowing crossborder electricity transfers, in this case, through a proposed subsea cable. A day-ahead market simulation is conducted to determine the impacts of the proposed interconnector on electricity prices in Iceland and the United Kingdom, as well as the import and export volumes of the interconnector. The simulation is carried out for two scenarios, where the first scenario provides a baseline simulation relying on the existing underlying data, while the second scenario is based on 2030 electricity market targets for both countries. The simulation does not take into account the interplay of intraday, financial or balancing electricity markets. The day-ahead market simulation shows that with an interconnector connecting the United Kingdom and Iceland, during the simulation period, using the current market baseline in the first scenario the electricity market prices would be higher in the United Kingdom than in Iceland. In the second scenario, where the electricity production and demand volumes increase, the simulation indicates that the electricity prices would be lower than in the first scenario in both countries and lower than actual prices without an interconnection in the United Kingdom. The interconnector is simulated for summer and winter periods and in both scenarios, Iceland is electricity exporter in winter and the United Kingdom only in summer. The electricity interconnector enhances the security of electricity supply in both Iceland and the United Kingdom, especially benefiting Iceland, integrating it to a wider electricity market. The interconnector allows transferring the electricity between countries and complementing their diverse electricity production assets and allowing electricity transmission during periods when domestic electricity production is insufficient.
  • Ympäristöön, yhteiskuntavastuuseen, ja hyvään hallintotapaan liittyvät kriteerit kiinteistösijoittajien päätöksenteossa
    (2025-02-18) Lahikainen, Otto
     School of Engineering | Master's thesis
    Global warming and limited natural resources have forced society to change and has forced people to think more sustainably. One of the most notable energy consumers and emitters are buildings, accounting for almost 40% of all greenhouse gas emissions in Finland. This has forced the real estate sector to change and environmental, social and governance (ESG) policies have found their way into professional real estate business. The aim of the study was to find out what kind of ESG criteria the professional real estate investors use in Finland. The study was conducted as a qualitative study and the data was collected with thematic interviews from six professional real estate investors managing a total of over 160 billion euros in real estate assets. The interviewed organizations represent well-known players in the industry, increasing the reliability of the results. The study found that most actively used ESG criteria are related to energy efficiency, heating, carbon emissions (CRREM), environmental certifications and environmental or climate risk management. Especially, the energy consumption and minimisation of carbon emissions were considered important, due to development of EU taxonomy, the Sustainable Finance Disclosure Regulation (SFDR) and the Paris Climate Agreement.
  • Vaativien rautatiehankkeiden kustannustehokas läpivienti hankeosittelun avulla
    (2025-01-27) Hasegawa, Samu
     School of Engineering | Master's thesis
    Railways are part of the vital ‘veins’ of the transport system, without which society cannot work. In addition to that, the railways play a significant role towards green transition, strengthening competitiveness and keeping the vitality of several areas. However, many railway projects, especially large-scale and difficult ones, are prone to three different failures: overbudgeting, schedule delay and failure in achieving the promised effect. This master’s thesis aimed for findings that help to optimize even the most difficult railway projects with the help of literature, case study and interviews. The goals of the study can be divided into three themes: 1) Optimization of the management and channeling of difficult railway projects with Lean, breakdown structures and combining different phases, 2) finding an alternative scenario for a case study project (Tampere-Jyväskylä planning and ground surveying services 2023-2026) from the beginning to the present day, offering suggestions for the current planning processes and future phases, and finally 3) offering other suggestions for optimizing Finnish railway projects, mainly on planning and designing phases. As the answer for the first theme, the following is suggested: Implications of the Lean construction practices, especially the concept of Kaizen, and breakdown structuring from different perspectives must be utilized in practice. In addition to that, it was found that the general plan (Yleissuunnitelma) and railway plan (Ratasuunnitelma) can be further procured as a single assignment. For the case project, it would have been better to create an alliance project for the earlier planning phases and focus more on Kaizen and collaboration (incl. stakeholders) in the current design phase. For the next phases (final designing and construction), the suggested form of the project is project management procurement, where the client procures a project management contractor that will split the project into suitable pieces. For the other suggestions on the Finnish railway projects, it is advised to re-examine the current long-term transport system plans and emerging project companies and effectively prevent and solve errors by examining the root causes of miscalculations and different behavioural biases.
  • ​Scale-effect in the shear strength of fresh fractures in Kuru granite​
    (2025-02-24) Anttilainen, Arttu
     School of Engineering | Master's thesis
    Abstract Rock joints have a large effect on the mechanical and hydraulic properties of rock mass. The characterization of rock mass requires assessment of jointing and the properties of joints. It has been shown that the shear strength of joints depends on scale and that most often, the shear strength of a joint decreases as the joint surface area increases in a negative scale effect, but results in literature are inconclusive. The scale effect on shear strength of fresh, artificially created fractures in Kuru granite was investigated with shear tests on five samples of different sizes: 95 x 95, 150 x 150, 200 x 200 mm and two 250 x 500 mm samples sheared in different directions. In addition to the five samples, the results were compared to results from two samples with sizes of 250 x 250 mm and 1000 x 2000 mm which had been tested in earlier studies. The fracture surfaces of the samples along with their physical aperture were captured with photogrammetry. The peak shear strength was predicted using Barton-Bandis- and revised Johansson-Stille failure criteria. Roughness was characterized with both 2D profiles using the Root mean square (Z2) and modified root mean square (Z’2) methods along with directional roughness metrics calculated from meshes of the fracture surfaces. A clear negative scale effect was observed with peak shear strength decreasing as joint size increased. Results showed that well mated joints can produce a strong negative scale effect in low stress conditions despite earlier studies indicating the contrary. The change in shear strength correlated more with change in joint surface area than change in joint length. Tilting played a role in the tests and resulted from the samples having different geometries and test conditions which allowed rotation of the samples. The most accurate estimate of peak friction angle was achieved using Barton-Bandis criterion with roughness through Z2’, with an 4,7 % average absolute error for all samples. With the revised Johansson-Stille criterion the corresponding error was 5,5 %. For only the large end of samples, the error with Barton-Bandis with roughness from Z2’ was 2,6 %. The corresponding error with Johansson-Stille criterion was 2,2 %.
  • Teollisuusrakennuksen jäykistysjärjestelmä maanjäristyskohteessa
    (2025-02-21) Ritakallio, Santeri
     School of Engineering | Master's thesis
    This thesis explores the differences between elastic and dissipative seismic steel frames. The focus of the thesis is concentrically braced frames. Frames designed as elastic have to be designed to resist higher seismic loads, but in general design standards do not place many special design requirements for such frames. Frames designed as dissipative can be designed for reduced loads, but they have to fullfill several design requirements to ensure ductility. The goal of this thesis was to investigate, if it is possible to use dissipative design to gain advantage as for example reduction in used material, taking the special design requirements and more challenging design procedure into account. Based on the case-example studied for this thesis, at least for a small structure dissipative design does not produce more economic design. Although loads on the braced frame are less, slenderness limits imposed on the vertical bracing lead to larger brace sizes. In addition, to ensure ductility, special load cases have to be taken into account, which lead to the scenario where especially the frame column profile sizes become significantly larger.
  • Linear Optimisation Model for Analysing Electricity and Hydrogen Production Pathways for Finland, Sweden, and Norway until 2060
    (2025-02-21) Tarvainen, Sami
     School of Engineering | Master's thesis
    This master's thesis introduces a linear optimisation model to study the impact of investments costs on the development of low-carbon electricity and hydrogen production systems in Finland, Sweden, and Norway. Three cost scenarios are developed for variable renewable energy (VRE), including wind and solar, as well as for electrolysers and hydrogen storages, to reflect the parametric uncertainty associated with these technologies. A wind and hydro-dominated power sector, coupled with additional flexibility options, becomes the optimal system design in most scenarios by 2060. Nuclear power capacity decreases from its current level in all scenarios except for two, which assume high capital costs for VRE sources. CCGT-H2 turbines provide significant backup capacity in Finland and Sweden across all scenarios, indicating that hydrogen can serve as an effective solution for seasonal storage of electricity. Higher costs of hydrogen technologies shift flexibility from the hydrogen to the power sector, manifesting as higher electrolyser capacity factors, increased VRE curtailment, and greater electricity transmission capacity. Substantial hydrogen pipeline capacity between Finland and Sweden is only installed in certain scenarios. Electrolysis-based hydrogen production reaches prices of 1.4-2.4 €/kg by 2060, suggesting that electrolysis can replace current grey hydrogen production and contribute to the decarbonisation of hard-to-abate sectors.
  • Väestödynamiikan muutokset pääkaupunkiseudulla vuosien 2017 ja 2023 välillä
    (2025-02-24) Salmela, Milla
     School of Engineering | Master's thesis
    Cities and their population are an important part of a functioning society. According to a UN report, 55 percent of the world’s population lived in cities in 2018. However, the structure and population dynamics of cities are constantly changing. In addition to static study methods, the structure and population dynamics of cities can also be studied dynamically. One way for dynamic analysis of the cities is the use of mobile phone data. The aim of this study is to answer two research questions: 1.) What changes have happened in population dynamics in the Helsinki Metropolitan Area between years 2017 and 2023 based on the mobile phone data, and 2.) How to combine and use two different spatial data layers that contain data in different spatial units to do a temporal comparison? There were two different mobile phone datasets used for this study. The first dataset is from the year 2017 and it has been collected from the data of a mobile phone operator. The second dataset is from the year 2023 and it has been collected based on the coordinates data from mobile phone applications. The programming language Python was used to preprocess datasets before the analysis, and the analysis itself was also done using the Python. The research methods used in this study were a comparative analysis and LISA analysis. From the results it can be seen that several changes have happened in population dynamics in the Helsinki Metropolitan Area between year 2017 and 2018. The results also showed that it is possible to use two different datasets that contains data in different spatial units for the comparison in this study.
  • Tekoälyn hyödyntäminen suunnittelunohjauksessa
    (2025-02-21) Raunemaa, Emil
     School of Engineering | Master's thesis
    Challenges in design management within the construction industry include issues such as poor information flow and difficulties in managing design changes. The advancement of artificial intelligence (AI) has opened new possibilities for addressing these challenges, but there is still limited research on its application in design management within construction companies. This thesis aims to explore how AI can be utilized in design management, particularly in manual and repetitive tasks. The study identified design management tasks where AI could add value, such as managing design input data and design changes, reviewing designs against technical requirements, generating meeting minutes, and verifying invoices from designers. The research also tested AI performance in these tasks and assessed its applicability to the practical needs of construction companies. The thesis follows a Design Science Research approach. Data collection included a literature review, a survey, interviews within the case company, and observations. Testing demonstrated that AI performs well in processing structured and organized data, such as managing design changes and generating meeting minutes. However, in more technically complex tasks, such as analyzing the technical content of 3D models and drawings, AI performance remained limited. Based on the findings, AI can support design management, particularly in automating routine tasks. However, its effectiveness currently depends heavily on the structuring and clarity of the data, as well as the quality of the prompts given. The potential applications of AI in design management will expand significantly as its ability to interpret technical content improves. This research provides a foundation for further studies that can deepen the understanding of AI’s role in developing and applying design management in the construction industry.
  • Multimaterial printinghead for biobased foams
    (2025-02-13) Mäntysaari, Verneri
     School of Engineering | Master's thesis
    3D printing is a rapidly developing subsection of manufacturing and it’s being leveraged into ever wider range of fields. But why stop at third dimension? This project’s aim was to enable further research into innovation of adaptive structures that change based on environmental factors, such as moisture and ambient heat, and to do this by creating a simple base prototype from which to build up from. This thesis is a documentation of designing, construction, and evaluation of multimaterial printinghead, which can switch between 2 materials during the printing process. The to be used are biobased foams, which are primarily com-prised of methyl cellulose and wood fibre, coming together as a building mate-rial that is 90% air. For the project comprehensive research on different aspects of 3D manufac-turing was conducted. These aspects included the effect that different materi-als used in 3D printing have in selection of the printing method and the effects the manufacturing methods have on the material at hand. The prototype was tested to validate its use by comparing different aspects of the test to the needs of manufacturing a selected target printing pattern. These aspects included the flow characteristics of the biobased foams being used as a material, the effect the prototype has on the material flow, and com-bination of these in the form of creating the selected printed patterns with multiple layers. The prototype successfully extruded prints that had 7 mm diameter with ac-ceptable variance in stability, was able to control the extrusion of the prints with acceptable accuracy and was able to bridge gaps of 20 mm in length to create multilayered 3D printing patterns. The results indicate that the project was a success as the needed parameters for the selected test print were met. Success of the project opens doors for further research to be built upon the findings to enhance the material properties, further improve the prototype capabilities, and investigate the structural properties of the adaptive structure patterns.