Publikationer från Uppsala Universitet
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Probabilistic Imbalance Price Forecasting and a Study of Sudden Price Shifts
No full textA fundamental requirement of the power grid is maintaining a balance between consumption and generation. When the balance is not fulfilled, the actors responsible for the imbalance are charged fees based on an imbalance price determined after the delivery period. Consequently, imbalance prices play a crucial role in the electricity market, and there is a need for good-quality imbalance price forecasts. This thesis project first focuses on probabilistic forecasting of imbalance prices using four different models: Quantile Regression, Quantile Regression Forest, a Probabilistic Neural Network, and an ARMA model. These models were evaluated on Finnish imbalance price data of 2024, using metrics such as Pinball Loss, Continuous Ranked Probability Score, and Probability Integral Transform Histograms. A novel metric, the Relative State Performance Score, was introduced in this thesis to evaluate the prediction of imbalance direction. The evaluation demonstrated that Quantile Regression and Quantile Regression Forest had the best error metrics and the best shape of the forecast. In contrast, the ARMA model performed poorly overall but proved promising in predicting the direction of imbalance. The second focus of the project is on a regulatory change in Finnish imbalance pricing introduced on June 12th, 2024, which caused a change in price behavior. These cases of change pose challenges for handling such a price shift from a forecasting perspective. Three different methods to handle a shift were examined through different traits using artificially generated price shifts: 1) Static Training Window, 2) Dynamic Training Window, and 3) Binary Signaling. In terms of adaption, the Dynamic Window method yielded the best results, especially for more severe shifts. By examining the models' reaction to the shift, e.g., by overconfident predictions, the results showed different properties for the underlying models, but overall, the Binary Signaling method avoided overconfident predictions
Cytokinesis in Suspension : A Distinctive Trait of Mesenchymal Stem Cells
No full textMesenchymal stem cells (MSCs) have a broad clinical potential, but their selection and expansion on plastic cause unknown purity and phenotypic alterations, reducing therapy efficiency. Furthermore, their behavior in non-adherent conditions during systemic transplantation remains poorly understood. The sphere formation from single cells is commonly used to assess stemness, but MSCs lack this ability, raising questions about their anchorage dependence for proliferation. We investigated whether bone marrow-derived MSCs can complete cytokinesis in non-adherent environments. Primary human and mouse bone marrow-derived MSCs were synchronized in early mitosis using nocodazole and were cultured on soft, rigid, or non-adherent surfaces. Both human and mouse MSCs displayed an ALIX (abscission licensor) recruitment to the midbody 40-90 min post-nocodazole release, regardless of the substrate adherence. Cells maintained for 4hr in the suspension remained viable, and daughter cells rapidly migrated apart upon the re-adhesion to fibronectin-coated surfaces, demonstrating cytokinesis completion in suspension. These findings distinguish MSCs from fibroblasts (which require adhesion for division), provide a more general stemness feature, and suggest that adhesion-independent cytokinesis is a trait relevant to the post-transplantation survival and tissue homing. This property may offer strategies to expand MSCs with an improved purity and functionality and to enhance engraftment by leveraging cell cycle manipulation to promote an early extracellular matrix deposition at target sites
Scalable Vocabulary Pruning for Large-Scale Chinese Word Segmentation on GDELT Ngram 3.0
No full textThis study addresses the challenge of Chinese word segmentation (CWS) in the only open, large-scale, real-time multilingual news dataset: GDELT Ngram 3.0. Conventional CWS systems are not designed for the structured and redundant format used in GDELT Ngram data and face limitations when scaled to this setting. To address this, a PySpark-based segmentation approach is proposed and evaluated across multiple data formats, prioritizing processing efficiency while maintaining acceptable segmentation quality. This approach incorporates scalable algorithms for the distributed computation of word boundary scores, utilizing frequency- and association-based statistical measures. Experiments demonstrate that the PySpark-based approach outperforms existing efficiency–performance trade-offs on GDELT Ngram-formatted evaluation data synthesized from standard CWS test-sets, effectively establishing a new Pareto frontier. It achieves an F1 score of 52%, with 64% recall and 44% precision, while delivering nearly twofold speedup over the fastest conventional system. Trade-off analysis on a development set further reveals that, at approximately 95% recall, the proposed pruning method can reduce the empirical candidate space by 70% and the vocabulary size by 99.85%. These findings validate the feasibility of real-time, distributed CWS for massive streaming news datasets and lay the groundwork for extending GDELT Ngram 3.0 with segmented word Ngram data for scriptio continua languages in the future
Optimal offering and operation strategy for hybrid power plants in hour-ahead mFRR energy activation markets with guaranteed service provision
No full textUtility-scale renewable hybrid power plants (HPPs) have emerged as promising electricity generation resources by combining multiple renewable generation technologies and storage. However, due to overplanting and co-location, storage size is usually smaller than that of renewable resources, which imposes challenges for HPP in providing reliable balancing services. This paper presents a novel model for optimizing the offering and operation of HPPs in hour-ahead manual frequency restoration reserve (mFRR) energy activation markets, with a focus on guaranteed service provision. The model takes into account uncertainties from wind power generation as decision-independent uncertainties, and considers the uncertainties related to the activation of mFRR to be influenced by the offering decisions, leading to decision-dependent uncertainties. The proposed model utilizes a robust two-level optimization approach, where the first level focuses on hour-ahead offering and operation, and the second level handles generation re-scheduling. Then, to ensure the computational efficiency with 15 min resolution, a modified column and constraint generation algorithm is proposed to solve the model. A comparative analysis reveals that the HPP with the proposed model can deliver upward and downward mFRR in 94% and 99% of the activated time, respectively. It meets transmission system operators' required 90% reliability
Perceptions of Empathic and Compassionate Healthcare Encounters : An International Exploratory Qualitative Descriptive Study
No full textBACKGROUND: Empathy and compassion are integral to person-centred care. Contemporary literature also provides evidence of the impact of empathic and compassionate care on patient outcomes, including enhanced satisfaction with care and improved patient safety. Notably, a previous scoping review identified only a limited number of studies exploring patients' experiences of empathic and compassionate care, underscoring the need for further research on patients' and their significant others' perspectives and experiences of empathic and compassionate healthcare encounters. OBJECTIVE: The aim of this paper is to explore patients' and their significant others' perceptions of empathic and compassionate healthcare encounters. METHODS: This qualitative descriptive international survey recruited people who were willing to report on a personal experience with a healthcare professional that demonstrated positive or negative examples of empathic and/or compassionate care. Data were analysed using Framework Analysis. RESULTS: A total of 84 participants from the Pacific region, the United States of America, and Europe reported encounters with nurses, doctors, allied health professionals, and multidisciplinary teams. Analysis revealed four overarching themes: (1) Verbal and non-verbal communication; (2) Clinician attitudes and attributes; (3) The power of small, thoughtful gestures; and (4) Enduring impact of empathic care. CONCLUSIONS: To promote empathic and compassionate care, there needs to be a holistic focus on practitioner communication across the bio-psycho-social-spiritual domains. When these elements are included in interactions with patients and their significant others, healthcare providers can have a powerful and long-lasting impact on people's experiences and health outcomes
“Jag vill påverka världen - åt ett bättre håll” : En geografisk studie av det lokala engagemanget för global klimaträttvisa hos unga i Uppsala
No full textDenna studie ämnar undersöka engagemanget för klimatfrågan bland unga vuxna i Uppsala i en tid där miljöaktivism på många sätt motarbetas. Forskningsfrågorna handlar om varför de engagerar sig, hur de upplever att de kan påverka och på vilket sätt deras vardag präglas av klimatförändringar. I studien har semistrukturerade intervjuer används som metod för att samla in material till resultatdelen. Åtta intervjuer har genomförts med unga som är engagerade i fyra olika klimatföreningar i Uppsala. Klimatföreningarna är Klimatstudenterna, Fridays for Future, Fältbiologerna och Grön Ungdom. Resultatet visar att unga i klimatorganisationer i Uppsala påverkas mycket av klimatförändringar genom kommunikationsnätverk och de globala processer som binder ihop världen. Deltagarna i studien får mycket information om klimatförändringar och dess orättvisa konsekvenser vilket leder till att de engagerar sig för att skapa klimaträttvisa. Intervjupersonernas engagemang motiveras av klimatångest och ilska mot politiker som inte gör tillräckligt för klimatfrågan. De upplever inte sina möjligheter att påverka som så stora, men anser ändå att det är väldigt viktigt och givande att engagera sig för klimatfrågan.
Functions of paradata in data papers
No full textPurposeThe purpose of this article is to increase our understanding of data papers as research narratives, with a focus on the functions that paradata - information about data creation and management processes and their underlying reasons - have, apart from describing data processes.Design/methodology/approachSeven papers from archaeological data journals were selected based on the number of citations they have received specifically for the use of their associated data. The paradata in the seven papers were analysed through close readings of them as narratives, and prominent functions were identified and examined.FindingsThree expressive paradata functions were found in the data paper narratives, contributing to the papers' arguments for the usefulness of the datasets, to the tone of the data papers and to the papers' construction of credibility.Originality/valueWe are aware of no previous studies of paradata as part of data paper narratives or of any studies of data papers employing close reading as an analytical tool
Krediter i flödet : Unga vuxnas attityder till konsumentkrediter.
No full textI takt med att FinTech-företag marknadsför tjänster som erbjuder konsumentkrediter i sociala medier, väcks frågor om hur det påverkar ungas attityder till kreditanvändning. Syftet med följande studie är att undersöka hur FinTech-företags kreditreklam påverkar unga vuxnas attityder, med stöd i Ajzens tredelade attitydmodell. En enkätundersökning genomfördes med 150 respondenter i åldern 18-25 år. Resultaten visar att unga vuxna exponeras frekvent för reklam som framställer konsumentkrediter som smidiga och riskfria. Trots det uppvisar många en reflekterande och kritisk hållning, där risker som överkonsumtion och ekonomisk ohälsa lyfts. Samtidigt kunde inga starka samband identifieras mellan graden av exponering och attityd. Studien visar att kreditreklam påverkar attityder genom subtila inramningar, men att unga inte är passiva mottagare. De tolkar budskapen utifrån egna erfarenheter och värderingar. Analysen betonar samspelet mellan attitydkomponenterna i formandet av synen på konsumentkrediter
Making Sense of Uncertainty : Narratives in Swedish Businesses under Geopolitical Uncertainty
No full textIn an era of growing geopolitical uncertainty, this study explores how Swedish business leaders make sense of uncertainty triggered by the renewed U.S. tariffs and protectionist trade policies. Drawing on theories of uncertainty, sensemaking, and strategic narratives, this study investigates the interpretive processes through which leaders perceive, frame and communicate external threats. Using a qualitative multi-case study design, we analyze publicly available statements from business leaders of eight Swedish export-oriented companies. The data was collected through company reports and media sources and analyzed using thematic analysis. This document-based approach enabled us to trace how narratives are constructed in real-time public discourse. Our findings show that different forms of uncertainty trigger different sensemaking processes and narrative framings. While some firms construct optimistic and resilient narratives to maintain internal and external confidence, others frame the situation as disruptive. The study highlights how business leaders use language, emotion, and framing to navigate complexity and influence stakeholder interpretation. This research contributes to the understanding of how strategic narratives are constructed in times of geopolitical uncertainty.
Outcomes of Single or Two Stage Brachiobasilic Arteriovenous Fistula : A Nationwide Swedish Registry Study
No full textObjective Creation of a brachiobasilic arteriovenous fistula (BBAVF) can be performed as either a one or two stage procedure; however, evidence for the best technique is conflicting. The aim of this national registry review was to determine whether functional outcomes favoured either method. Methods This was a retrospective observational study with data from the Swedish Renal Registry. BBAVFs created in patients aged ≥ 18 years between 2011 and 2019 were included and were categorised as one stage (BB1) or two stage (BB2). Outcome, patency, and complications were captured from creation onwards, as were all open and endovascular repeat procedures. Results BB1s (n = 224) were more common than BB2s (n = 83). Of the BB2s, 66 (80%) were transposed in the second stage. The most common reason for not performing transposition was occlusion (n = 10). The median follow up was two years (interquartile range [IQR] 0.8, 4.2). Overall, 31% of BBAVFs were never used. Vein stenosis was common, seen in 157 BB1s (70%) and 40 BB2s (48%). The incidence of endovascular interventions per patient year was two times higher in BB1s than BB2s (0.6 vs. 0.3). Primary patency at one year was 39% and 54% in BB1 and BB2, respectively (p = .002). Secondary patency at one and three years was similar between groups (BB1 81% and 69%, and BB2 82% and 78%; p = .14). Diabetes as a comorbidity and female sex were associated with worse patency, but body mass index ≥ 30 kg/m2 was not. Creation pre-dialysis did not affect patency. The median time from creation to first puncture was 73 days (IQR 51, 157) and 141 days (IQR 105, 225) for BB1 and BB2, respectively. Conclusion The two stage method had superior primary patency, counterbalanced by two operations. Long term patency was equivalent for the two surgical techniques. The incidence of endovascular re-interventions was high, and BBAVFs were less usable in females and patients with diabetes as a comorbidity