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Brain Tumor Segmentation using Deep Learning: A Hybrid Model.
No full textAccurate brain tumor segmentation from MRI scans is crucial for diagnosis, treatment planning, and prognosis. However, manual segmentation is labor-intensive, prone to variability, and susceptible to errors, emphasizing the need for automated solutions. This study proposes the development and evaluation of deep learning architectures for brain tumor segmentation using the BraTS 2020 dataset. We propose and compare two approaches: (1) a standalone 3D U-Net, which processes 3D MRI volumes, and (2) a hybrid 2D model that combines a pre-trained VGG19 encoder with a U-Net decoder for 2D slice-based segmentation. The hybrid model leverages VGG19’s powerful feature extraction capabilities while maintaining the structural advantages of U-Net. To optimize the hybrid model, we applied a data transformation strategy that transforms volumetric MRI data into 2D slices, aligning with the inherent architecture of VGG19. The segmentation models were trained and evaluated using three out of four MRI modalities from the BraTS 2020 dataset, T1Gd, T2, and FLAIR, which provide complementary information for accurate tumor structure identification. Performance evaluation showed that the 3D U-Net exhibits limitations in segmenting tumor subregions, achieving Dice Similarity Coefficients (DSC) of 0.7870 (Necrotic and Non-Enhancing Tumor Core, NCR/NET), 0.8609 (Edema, ED), and 0.8058 (Enhancing Tumor, ET), with corresponding Intersection over Union (IoU) scores of 0.6489, 0.7558, and 0.6747, respectively. While the model demonstrates high specificity across all tumor classes, its lower sensitivity suggests the need for improvements to detect all instances of pathological tissue more effectively. On the other hand, the hybrid U-Net + VGG19 model demonstrates clearly superior segmentation results, outperforming many existing methods. It achieved DSC scores of 0.9078 (NCR/NET), 0.9245 (ED), and 0.9175 (ET), consistently exceeding 0.91 across key tumor subregions. Additionally, the hybrid model achieves superior segmentation performance across the three tumor structures, whole tumor (WT), tumor core (TC), and enhancing tumor (ET), achieving DSC scores of 0.9620, 0.9550, and 0.9175, respectively. As observed from the performance evaluation results of the models, the hybrid U-Net with VGG19 provides a computationally efficient and highly accurate approach for brain tumor segmentation
Towards More Effective Collaboration Within the OCC : Social Network Analysis in the Context of Knowledge Management
No full textThe aim of this master's thesis was to investigate means to enhance the collaboration among the control rooms and supporting functions in Metropolitan Area Urban Transport Ltd. In addition to improving collaboration, research was conducted on the significance of tacit knowledge. The theoretical foundation of the work focused therefore on the concept of knowledge management, particularly knowledge sharing and tacit and explicit knowledge, as well as social network analysis methods.
Collaboration is an essential component that significantly contributes to operating efficiently. A fundamental aspect of collaboration is the seamless sharing of information, along with the diverse methods and tools employed to facilitate this process. Within the control room environment, the ability to share information efficiently and in a timely manner is of extreme importance as this practice not only enhances the decision-making process but also plays a critical role in managing traffic effectively while prioritizing safety.
The material used in the work was collected by producing a survey, which the 102 members of the focus group were asked to respond to. By analyzing the data collected from the initial situation, it was possible to interpret the current state of information and knowledge management, as well as the key areas for development, which included the inadequacy of operational models and systems, as well as the need to improve internal collaboration across the entire organization.
Through the method of social network analysis, it becomes evident that there are no significant deficiencies that can be observed within the network of the focus group. This analysis provides valuable insights into the interactions and relationships among the participants. However, it is important to highlight that only 67% of the participants took the time to respond to the survey. While an excellent response rate, it imposes a limitation on the ability to present a comprehensive and complete depiction of the network. The lack of full participation may mean that certain perspectives or connections within the network remain unaccounted for, potentially biasing the overall understanding of the group's dynamics.
Implementing a similar network analysis in a non-anonymous manner is highly recommended, particularly when considering the potential for future development and growth within the organization. This approach allows for a more detailed understanding of the network dynamics and can lead to more informed decision-making processes. Conducting a comprehensive network analysis that encompasses the entire organization would also be considered a recommendable action. Such an analysis would not only provide insights into the various interconnections and relationships within the organization but also help in identifying areas for improvement and opportunities for collaboration across different departments. By taking this holistic view, the organization could better leverage its resources and enhance overall efficiency
“If I Were a ‘Finnish Woman’, He Could Not Insult Me Publicly” : An Intersectional Analysis on the Experience of Social Isolation and Integration Among Bangladeshi Migrant Women in Finland
No full textThis study explores the intersectional experiences of social isolation and integration among Bangladeshi migrant women in Finland, focusing on how their gender, ethnicity, religion, and migration status contribute to compounded exclusion. Despite an increasing body of literature on migration, few studies have specifically addressed the complex, intersecting identities of Bangladeshi women within the Finnish context. Previous research has largely focused on economic integration, often overlooking the social, cultural, and psychological dimensions of migration. Moreover, while migration studies emphasize the general challenges faced by immigrant populations, they fail to address how these challenges uniquely affect women from non-Western backgrounds. This research aims to fill this gap by analyzing the impact of social isolation in the integration process of Bangladeshi migrant women, using qualitative methods, including semi-structured interviews with Bangladeshi women living in Finland. The findings reveal that the intersection of multiple marginalized identities leads to heightened experiences of exclusion, which in turn delays or complicates their integration into Finnish society. These findings underscore the need for gender-sensitive, intersectional approaches to migration policy and highlight the importance of social integration programs that go beyond economic integration. The implications of this study are significant for policymakers, social workers, and academics seeking to develop more inclusive strategies for the integration of immigrant women
Activity-Based Costing for Interorganisational-Oriented Cost Tracking and Transparency - An Action-Oriented Case Research
No full textThis thesis investigates whether Activity-based costing can be used in interorganisational settings and whether it could help enhance cost tracking and cost transparency in complex interorganisational networks. Traditional cost accounting systems often fail to capture the indirect and shared costs. These are the costs caused when two or more organisations collaborate in the same value chain. Organisations are becoming more decentralised while being more connected. To sustain and bolster strategic decision-making, as well as financial accountability, a more dynamic and granular approach to cost allocation is required.
The thesis employs an action-oriented research (AOR) methodology, melding theoretical reflection with empirical intervention. An action-oriented case study was developed in collaboration with a multinational organisation. Stakeholders at the organisation worked closely with the researcher to iteratively develop and test the use of ABC in a real organisational context. The empirical material includes internal documents of the organisation, interviews with key managers and the researcher’s participatory observations.
The resource advantage theory and dynamic capabilities theory constitute the theoretical framework of the thesis. It is believed that ABC can give an idiosyncratic advantage through the discovery and modification of previously unnoticed costs to make them visible to agents. How ABC can be altered to monitor costs at interorganisational level; and how does ABC influence perceptions of whom costs are charged to in an interorganisational network?
The research outcomes demonstrate that ABC offers clearer cost visibility and better allocation accuracy. However, whether it is used for interorganisational applications will depend on the extent to which the partners involved are aligned with one another, and whether adequate data is available. Moreover, both the partners must be willing to share cost data with each other in an open and transparent manner. The researcher was also noted for facilitating dialogue and learning in the action-oriented case study with research knowledge and skills.
The thesis expands the field of interorganisational cost accounting literature by exploring how ABC can be employed as a control tool for network-level costs in addition to a control tool. Also, it highlights the need for a cooperative structure, trust, and continuous engagement when applying ABC beyond an organisation
Comparative Risk Analysis for the Fukushima Disaster
No full textThe Fukushima nuclear incident has highlighted the urgent need for effective risk management strategies, both to prevent high-consequence industrial disasters and to mitigate their consequences. In this thesis, we undertake a critical comparison among prominent methodologies used to perform risk assessment, namely FTA, ETA, HAZOP, and Bowtie Analysis. These are then reviewed in light of the Fukushima disaster to explore how each provides insight into risk identification, root cause analysis, and mitigation strategy. Using each of these frameworks, we cover complex and interlaced risks and identify the strengths and limitations of each, along with their collaborative potential. Such findings will enable critical infrastructure owners to apply better risk management strategy administrations to cope more effectively
with any potential catastrophic situation
The Proposed International Anti-Corruption Court (IACC): A Critical Examination of Immunity and Its Implications for Global Anti-Corruption Efforts
No full textThis master’s thesis extensively explores how the complex issue of immunity in international law challenges the establishment and effectiveness of the proposed International Anti-Corruption Court (IACC) and its aim of prosecuting grand corruption. The research using a doctrinal legal approach explores how the functional and personal immunity of high-ranking state officials poses a challenge to the court bearing in mind the history of the International Criminal Court (ICC) which the proposed court is being modelled on. The research further examined the conceptualisation of grand corruption as an international crime or crimes against humanity to bypass immunity and whether the current ICC framework could be interpreted to cover grand corruption. The thesis also explored whether grand corruption could be classified as official acts for applying functional immunity and the difficulty distinguishing between official and private acts concerning corruption cases. Overall the thesis found that despite its devastating impacts, grand corruption has not yet evolved into an international crime and the unsettled and controversial issue of immunity in international law poses a significant hurdle to the
proposed court’s effectiveness
Русско-шведский билингвизм и многоязычие в Финляндии : Три языковых портрета
No full textПредставленная читателю работа посвящена русско-шведскому билингвизму и присущему Финляндии многоязычию, в целом. Мы сконцентрировались на русско-шведской стороне, поскольку эта тема ранее не изучалась (и финский, и шведский язык являются государственными языками, однако шведоязычные финны являются языковым меньшинством, и в финском контексте их в рамках языковых исследований не обсуждают столь же активно, как финно-русских билингв). В данной работе мы представили лингвистическую теорию (объяснили понятие билингвизма и языковой личности, конкретизировали типы билингвов, варианты усвоения языка). В данном исследовании использовался метод языкового портретирования, который мы также подробно описываем, данный метод основан на метафорическом, символическом и ассоциативном мышлении респондентов. Задействована также практическая часть, – участники исследования, согласно используемому нами методу, раскрашивают / разрисовывают силуэт человечка, отталкиваясь от своего осознания данного им языкового репертуара. В данном исследовании были задействованы трое совершеннолетних информантов, трое молодых женщин в возрастном диапазоне от двадцати до тридцати двух лет с разными образовательными, семейными и языковыми бэкграундами. Результаты исследования показали, что языки, перечисленные в языковом реестре респондентов, были усвоены по-разному и используются в разных сферах жизни
Vimentin och 14-3-3 proteinerna samordnar lokaliseringen av YAP under sårläkning
No full textDefective wound repair, a consequence of underlying diseases, can lead to chronic wounds and fibrosis. One such disease is diabetes, which causes chronic wounds that may lead to amputations. To develop treatments, the mechanisms behind wound healing need to be elucidated. Vimentin is an intermediate filament that plays an important role in wound healing, which was observed in vimentin-deficient mice with delayed wound closure. Intermediate filaments are cytoskeletal proteins, which are important for the function and migration of the cells. Vimentin has been found to interact with Yes-associated protein (YAP), which is a transcriptional coactivator involved in proliferation and cell migration. Both YAP and vimentin have been shown to interact with the 14-3-3 proteins when phosphorylated. The 14-3-3 proteins bind to many different proteins important in cellular functions, such as the cell cycle and transcription. The 14-3-3 proteins interact with vimentin to stabilize its structure during cellular processes, such as migration and in response to injury. The 14-3-3 proteins regulate YAP, which regulates cell growth and survival. This thesis investigated the role of the 14-3-3 proteins in regulating YAP and how vimentin may play into regulating YAP. The thesis also studied the interaction between 14‑3‑3 and vimentin and how it plays a role in how the proteins regulate YAP
Gender co-construction and co-display in entrepreneurial pitching context : Towards a pluralistic perspective on gender research in entrepreneurship
No full textThis doctoral thesis explores the complex dynamics of gender in entrepreneurship, focusing on how gender is co-constructed and co-displayed in both the frontstage (public presentations) and backstage (preparation) of entrepreneurial pitching. By drawing on dramaturgy, gender as a social structure, and entrepreneurship-as-practice literature, the thesis also investigates how gender operates across individual identities, interactions, and institutional norms.
The thesis consists of three empirical studies, two of which were conducted in Finland, and one conducted in Finland and partly in Sweden. The thesis follows a qualitative research design and is strongly informed by poststructural feminist theory. The empirical data is varied, including pitching videos (n= 99 short pitches), interviews (n= 18), and observation note data (n=132 pages). The analysis approach is narrative and constructivist grounded theory.
The thesis contributes to gender and entrepreneurship research by showing how gender is embedded in entrepreneurial pitching performance and its practices both in the frontstage and in the backstage. It highlights the need to recognize and support diverse forms of entrepreneurial expression, especially those that do not conform to the dominant masculine ideals. By incorporating the perspectives of various entrepreneurial actors, the thesis highlights the need to adopt a pluralistic approach in entrepreneurship research. The research has societal implications by advocating for better awareness about gender issues in entrepreneurship, enabling entrepreneurial actors to reflect and initiate changes.Den här doktorsavhandlingen utforskar den komplexa dynamiken av genus i entreprenörskap, med fokus på hur genus gestaltas och framställs gemensamt i både frontstage (offentliga presentationer) och backstage (förberedelser) av entreprenöriell pitching. Avhandlingen bygger på litteratur om dramaturgi, genus som en social struktur och entreprenörskap som praktik och undersöker också hur genus tar sig i uttryck i olika individuella identiteter, interaktioner och institutionella normer.
Avhandlingen består av tre empiriska studier varav två har genomförts i Finland och en delvis i Finland och delvis i Sverige. Avhandlingen följer en kvalitativ forskningsdesign och tar avstamp i poststrukturell feministisk teori. Den mångsidiga empiriska datan består av pitchingsvideor (n=99 korta pitchar), intervjuer (n=18) och observationsanteckningar (n=132 sidor). Analysansatsen är narrativ och konstruktivistisk grundad teori.
Avhandlingen bidrar till genus- och entreprenörskapsforskningen genom att visa hur genus är inbäddat i entreprenöriellt pitching-framträdande och dess praxis både i frontstage och backstage. Den framhäver behovet av att erkänna och stödja olika former av entreprenöriella uttryck, särskilt dem som inte överensstämmer med de dominerande maskulina idealen. Genom att införliva olika entreprenöriella aktörers perspektiv framhåller avhandlingen behovet av att anta ett pluralistiskt tillvägagångssätt inom entreprenörskapsforskningen. Forskningen bidrar till samhället genom att förespråka bättre medvetenhet om genusfrågor inom entreprenörskap, vilket gör det möjligt för entreprenöriella aktörer att reflektera och införa förändringar.ei tietoa saavutettavuudest