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The Influence of AI-driven Personalized Content on Social Media Engagement : A Systematic Literature Review
No full textThrough artificial intelligence (AI), social media platforms can personalize content based on how users interact and what their preferences are. This thesis evaluates the impact of artificial intelligence-generated personalized content on social media metrics such as likes, comments and shares while relying on research documents from Springer, Science Direct, Scopus, and others. The research analyzes current trends, challenges, and strategies by investigating the integration between machine learning (ML), natural language processing (NLP), and generative adversarial networks (GANs) to upgrade user engagement methods. AI personalization delivers better user engagement through real-time content refinement, meaning it updates content instantly based on user actions. It also enhances segment generation, which groups users by their behavior for better targeting and predictive analytics helps predict what users want next, which result in more likes, shares and higher retention rates. However, AI-driven solutions face substantial ethical obstacles because of system biases, together with privacy risks and self-selected information bubbles. The implementation process faces challenges from technical obstacles, which include demanding computing power and difficulties interpreting results. Research offers solutions consisting of user-centered transparency methods alongside explainable AI solutions and combinations between human experts and artificial intelligence systems. The research findings demonstrated that ethical governance, together with user trust, must exist to enable long-term AI-driven personalization sustainability. This research supports the theoretical frameworks of the Technology Acceptance Model (TAM) and Uses and Gratifications Theory (UGT) to show how AI personalization meets user needs and encourages technology adoption. Based on these theories, it offers policy strategies to help governments ensure ethical AI use and build user trust
Models, Prompts, and Performance : A Dual-Factor Study of AI-Assisted Programming
No full textThis thesis evaluates how modern language-model assistants generate software and how the wording of user instructions affects the outcome. Three widely used models—OpenAI o3, GitHub Copilot, and GPT-4o—were asked to solve five non-trivial Python tasks that cover optimization, debugging, partial synthesis, full-program construction, and large-scale dynamic programming. Each task was presented under three prompt styles: minimal, basic, and in-depth. An automated harness measured execution time, peak memory, and six static code metrics, while hidden tests verified functional correctness.
The study shows that model choice and prompt richness interact strongly. The o3 model paired with in-depth guidance delivered the fastest, most maintainable, and best-documented code, cutting runtime on the hardest tasks by up to 45 percent and halving memory use on matrix multiplication. Copilot required the fewest corrective attempts and never failed a task, making its minimal-prompt mode the most dependable overall. GPT-4o trailed in reliability. Rich prompts generally improved speed and documentation across all models, yet they also triggered the single task failure observed.
A positive link emerged between maintainability index and runtime efficiency, suggesting that clear structure and high speed can coexist. Conversely, aggressive memory saving sometimes reduced maintainability. The findings recommend detailed prompts for expert users seeking maximum performance with o3, and concise prompts for novices relying on Copilot, while emphasizing continued need for testing and human review
Novel Value-added Applications for Cellulose Nanomaterials : Towards Optics and Electronics Applications
No full textAnthropogenic climate change is one of the biggest global challenges of the 21st century and a green transition is an imminent mitigation measure. One facet of the green transition is a shift away from petroleum-derived materials towards sustainable lignocellulosic biomass-derived materials, while maintaining economic output. However, the available biomass must be utilized wisely and efficiently in order to preserve biodiversity and the ecological balance. Therefore, it is critical to explore application areas for lignocellulosic biomass where low production volumes can lead to high derived value.
This work focuses on the utilization of cellulose from biomass in novel highvalue applications in optics and electronics. The materials of interest in this thesis were cellulose nanomaterials and cellulose derivatives. Cellulose nanofibrils (CNF) and cellulose nanocrystals (CNC) were used to fabricate optical films with tunable transparency and haze. Novel thermochromic films from CNF and CNC were produced with the addition of thermochromic (TC) particles to the films. TC particle-doped films exhibited a pronounced reversible black-to-colorless transition upon heating above a transition temperature. The optical properties of CNF-TC and CNC-TC hybrid films could be significantly altered by controlling the particle doping and the film temperature. This feature was harnessed in an all-optical light modulator device where IR light was modulated using visible laser light. Such films hold potential in various thermally-stimulated sensing systems such as temperature monitoring, energy saving, logistics, and smart labels.
Cellulose is a strong emitter in the Earth’s mid-infrared atmospheric transmission window of 8-13 μm, making it a suitable material for passive radiative cooling. Following this, CNF-TC films were explored for passive radiative cooling application taking advantage of both the intrinsic properties of cellulose and the thermochromic functionality provided by the TC particles. Thin silver coatings on CNF-TC films were also explored. Here, a change in film transmission and reflectivity upon thermal stimulus enabled weather adaptive space cooling. A cooling potential of 1-10 °C was measured with the films in laboratory conditions and up to 12 °C in outdoor field tests. The demonstrated films could be applied in cooling roofs and windows in living spaces and greenhouses.
Further, nanocomposite films of CNF and hydroxyethyl cellulose (HEC) were fabricated for application as printed electronic substrates. The CNF-HEC films offered beneficial features such as strength, ductility, conformability, highresolution printability, and biodegradability. The CNF-HEC films were successfully processed in a typical printed electronics fabrication flow, as used for conventional polymer substrates, to fabricate a prototype wearable electrocardiograph (ECG) device. End-of-life scenarios for the devices fabricated on the CNF-HEC films were studied to enable material recovery and avoid incineration or landfilling.
Finally, carboxymethyl cellulose (CMC) optical fibers were fabricated via wet-spinning and crosslinking of CMC hydrogels with aluminum ions. The novel biopolymer optical fibers were produced in a core-only architecture to facilitate environmental sensing capabilities. The CMC optical fibers acted as waveguides in the visible and near-infrared regions and were successfully demonstrated for touch and respiratory rate sensing. Additionally, short-range high-speed optical signal transmission was demonstrated in both air and water media. Such biobased and biocompatible CMC fibers can be applied in environmental sensing, health monitoring, and medical diagnostics.
This work opens new avenues for the utilization of cellulose-based materials in a variety of use cases spanning the optics, electronics, and construction sectors. Future work could focus on studying the durability of the cooling films, improving the reliability of electronic devices, and reducing the attenuation of CMC optical fibers. However, the most important aspect would be the upscaling and commercialization of the demonstrated materials and concepts.Klimatförändringar orsakade av människan är en av de största globala utmaningarna under 2000-talet. En grön omställning, där vi ersätter petroleumbaserade material med hållbara material från lignocellulosabaserad biomassa, samtidigt som vi bibehåller ekonomisk lönsamhet, är en viktig åtgärd för att begränsa dessa förändringar. Det är dock viktigt att använda biomassan klokt och effektivt för att bevara naturens biologiska mångfald och ekologiska balans. Därför är det avgörande att utforska användningsområden för lignocellulosabaserad biomassa där små produktionsvolymer kan leda till höga avkastningsvärden.
Detta arbete fokuserar på användningen av cellulosa från biomassa i nya värdefulla användningsområden inom optik och elektronik. De material som studerades var nanomaterial av cellulosa och cellulosaderivat. Cellulosa nanofibriller (CNF) och cellulosa nanokristaller (CNC) användes för att tillverka optiska filmer med justerbar transparens och diffus ljusspridning (haze). Nya termokroma filmer från CNF och CNC producerades genom att tillsätta termokroma (TC) partiklar. Dessa filmer visade en tydlig reversibel övergång från svart till färglös vid uppvärmning över en viss temperatur. De optiska egenskaperna hos CNF-TC- och CNC-TC-hybridfilmer kunde signifikant ändras genom att kontrollera partikeltillsatsen och filmtemperaturen. Denna egenskap användes i en ljusmodulator där IR-ljus styrdes med hjälp av synligt laserljus. Sådana filmer kan potentiellt användas i olika termiskt stimulerade sensorer för temperaturövervakning, energibesparing, logistik och smarta etiketter. Cellulosa är en stark emitter i jordens mittinfraröda atmosfäriska transmissionsfönster på 8-13 μm, vilket gör det till ett lämpligt material för passiv strålningskylning. Detta undersöktes med CNF-TC-filmer, där både cellulosans naturliga egenskaper och den termokroma funktionen hos TCpartiklarna bidrog till kylningseffekten. Tunn silverbeläggning på CNF-TCfilmer undersöktes också. Här möjliggjorde en förändring av filmens ljustransmission och reflektion vid uppvärmning det möjligt att anpassa kylningen efter vädret. En kylningspotential på 1-10 °C uppmättes i laboratorieförhållanden och upp till 12 °C i fälttester utomhus. Dessa filmer kan användas för kylning av tak och fönster i bostäder och växthus.
Vidare tillverkades nanokompositfilmer av CNF och hydroxietylcellulosa (HEC) för användning som substrat för tryckt elektronik. CNF-HEC-filmerna hade fördelaktiga egenskaper som styrka, duktilitet, formbarhet, tryckbarhet med hög upplösning och biologisk nedbrytbarhet. Dessa filmer bearbetades framgångsrikt i en typisk tillverkningsprocess för tryckt elektronik, för att tillverka en prototyp av en bärbar elektrokardiograf (EKG)-enhet. Återvinningen av material från dessa enheter demonstrerades som ett alternativ för att undvika förbränning eller deponering.
Slutligen tillverkades optiska fibrer av karboximetylcellulosa (CMC) genom våtspinning och tvärbindning av CMC-hydrogeler med aluminiumjoner. Dessa nya optiska fibrer konstruerades med en enkel kärna för att möjliggöra miljöavkänning. De optiska CMC-fibrerna fungerade som vågledare i det synliga och nära infraröda området och användes för avkänning av beröring och andningsfrekvens. Dessutom demonstrerades optisk signalöverföring med hög hastighet över korta avstånd i både luft och vatten. Sådana biobaserade och biokompatibla CMC-fibrer kan användas för miljöavkänning, hälsoövervakning och medicinsk diagnostik.
Detta arbete öppnar nya möjligheter för användning av cellulosabaserade material inom optik, elektronik och byggsektorn. Framtida arbeten kan fokusera på att studera hållbarheten hos kylfilmerna, förbättra tillförlitligheten hos elektroniska enheter och minska dämpningen hos CMC-optiska fibrer. Den viktigaste aspekten är dock uppskalning och kommersialisering av de demonstrerade materialen och koncepten.ei tietoa saavutettavuudest
A Reflection
No full textAs a scholarly approach, “lived theology” is still a loose and evolving paradigm not yet fully developed as a research field, and where definitions and methods are still open to discussion. This reflective text suggests a theoretical and theological framework for lived theology and suggests a working definition. The author proposes thinking of lived theology as simultaneously a particular understanding of the nature of theology, a scholarly enterprise and a vision for a better world. Lived theology, therefore, involves seeing theology as a living practice, paying attention to the theology of the living and the lived, and striving for a theology that is life-giving and life-affirming. With such an approach, theologizing processes of the first and second order are held together in the theological task, and a plethora of possible methods may be utilized to study theology. The author also points to the critical task of lived theology and its doctrinally shaped roots
Vi och dem? : En rapport om samhällspolariseringen i Svenskfinland
No full textei tietoa saavutettavuudest
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No full textThe aim of this study is to inquire what parents do, so that their children grow up bilingual. The aim is to reveal thoughts, attitudes and practices, not only of those who have accomplished their aim, and their children are bilingual today, but also of the fewer of them who have been unsuccessful. Ten interviews were analyzed with the narrative method and the account of the results consists of two types of themes: expected (big stories) and unexpected (small ones). In other words, some topics which arose in the interviews address core findings in bilingualism research while others set the present piece of research apart from other pieces and address more original topics or somehow atypical topics in the field. In total, nine findings are being discussed belonging in the thematic entities of both big and small stories. An example of the former category is the parents’ reflections on what they do and what they would be doing if they were given another chance to promote bilingualism. An example of the latter category is how two parents who have not achieved bilingualism explain this result. All in all, those parents who have been consistently reading stories to their children and have been travelling to the home country have had better outcomes and their children are progressing well in the minority language. If a parent has, or seems to have given up the use of their native language, children are left to their own devices and in the case of languages they end up using the majority language, Finnish (or Swedish), which they are taught at school. Finally, parents who have systematically sought for help have been able to tune purposes and practices to the advantage of the linguistic picture at home
Pressurized hot water extraction of spruce and birch bark : kinetics and properties of recovered materials
No full textBark is an abundant by-product of the forest industry, typically used for energy generation. Hardwood and softwood bark contain cellulose, hemicellulose, and lignin, as other plant biomass. However, in contrast to wood biomass, bark is rich in extractives and phenolic compounds, such as tannins, suberin, and waxes, which could be employed for potential substitution of petroleum-based materials in value-added products manufacture. As demand for alternatives to fossil-based products grows, efficient strategies for bark valorization are needed. This study investigates the kinetics of spruce and birch bark fractionation using pressurized hot water extraction (PHWE). Moreover, the properties of recovered materials were investigated in detail.
The primary objective was to evaluate the influence of extraction temperature and time on the yield and composition of soluble and solid fractions and to identify optimal conditions for maximizing recovery while preserving the functional value of the fractions. The study also examines the composition of solid residues and extracted materials, with particular focus on hemicellulose and lignin-rich fractions.
The results showed species-specific differences in extractability and composition. Removal of suberin from birch bark was necessary to allow accurate compositional characterization, particularly for lignin quantification. The results demonstrate the potential of PHWE as an effective method for bark fractionation and emphasize the importance of species-specific process optimization in biorefinery applications
Different constructions of the working electrode used in the novel coulometric signal transduction setup
No full textIn this research work, different constructions of the working electrode (WE) intended for use in the novel coulometric signal transduction setup were studied and evaluated. There were two primary strategies for the construction: (1) modification of the composition of the dummy membrane (DM), and (2) integration of a salt bridge filled with KCl solution. The analytical performance of each WE in detecting K+ was assessed by determining key analytical parameters such as, signal amplification, response time, sensitivity, linearity of the cumulated charge (Q) against the logarithm of K+ activity, and suitability of the fabricated WEs for sample solutions with and without the presence of high and constant BGE concentration, which were obtained through various electrochemical characterization techniques. Results from the electrochemical impedance spectroscopy revealed that changing the DM composition proved to be an effective approach in tuning the electrode resistance and capacitance which affects the time constant and response time of the WE. In the case of WE with a salt bridge, changing the concentration of the inner filling solution influenced the salt bridge resistance and low-frequency capacitance (CLF) values. In terms of assessing the suitability of the fabricated WEs in the novel coulometric signal transduction setup, results from chronopotentiometric experiments showed that all fabricated WEs responded with minimal sensitivity to changes in K+ concentration in both solutions with and without the presence of BGE. Moreover, the amount of accessible redox capacitance from PEDOT:PSS determined the magnitude of the generated current and charge signals as evident in the results recorded from the chronoamperometric and chronocoulometric addition/dilution experiments. In addition, the calibration curves of all the WE obtained during the sequential dilution experiments exhibited strong linearity between the total accumulated charge (Q) and logarithm of potassium ion activity (log aK+). Lastly, all fabricated WEs successfully detected smaller changes in analyte concentration regardless of the magnitude of the generated signals, demonstrating higher sensitivity of coulometric transduction method over potentiometric method
