Ore extensions of abelian groups with operators

Given a set A and an abelian group B with operators in A, in the sense of Krull and Noether, we introduce the Ore group extension B[x;\sigma_B,\delta_B] as the additive group B[x], with A[x] as a set of operators. Here, the action of A[x] on B[x] is defined by mimicking the multiplication used in the classical case where A and B are the same ring. We derive generalizations of Vandermonde's and Leibniz's identities for this construction, and they are then used to establish associativity criteria. Additionally, we prove a version of Hilbert's basis theorem for this structure, under the assumption that the action of A on B is what we call weakly s-unital. Finally, we apply these results to the case where B is a left module over a ring A, and specifically to the case where A and B coincide with a non-associative ring which is left distributive but not necessarily right distributive.CC BY 4.0</p

Robot digital twin systems in manufacturing : Technologies, applications, trends and challenges

The manufacturing industry is undergoing a profound transformation toward smart, digital, and flexible production systems under the Industry 4.0 framework. Within this paradigm, Digital Twin (DT) serves as a key enabler, bridging physical and digital domains to simulate, analyse, and optimise manufacturing operations. Concurrently, robotic systems, enhanced by smart sensor perception, Industrial Internet of Things connectivity, and adaptive control mechanisms, are increasingly deployed to handle complex and dynamic tasks. However, the evolving demands of the modern manufacturing industry require a high degree of flexibility and responsiveness, necessitating more intelligent solutions. The Robot Digital Twin (RDT) has emerged as a transformative approach, facilitating dynamic adaptation and continuous operational improvement. This review offers a comprehensive examination of the literature on RDT in manufacturing from both technology and application perspectives, aiming to provide insight for researchers and practitioners in Industry 4.0. The paper introduces a four-layer RDT system architecture and summarises how Industry 4.0 technologies, e.g., the Industrial Internet of Things, Cloud/Edge Computing, 5 G, Virtual Reality, Modelling and Simulation, and Artificial Intelligence, converge and influence the RDT system based on this architecture. Furthermore, the review covers domain-specific and system-level applications, such as assembly, machining, grasping, material handling, human-robot interaction, predictive maintenance, and additive manufacturing systems, with an analysis of their development status. Finally, the trends, practical challenges, and future research directions for RDT systems in manufacturing are summarised at different levels.CC BY 4.0© 2025 The Author(s)Correspondence Address: X.V. Wang; Department of Production Engineering, KTH Royal Institute of Technology, Stockholm, 10044, Sweden; email: [email protected]; CODEN: RCIMEThis research was supported by the EU Horizon Europe NEPTUN project (Grant Agreement: 101079398), the Swedish Digital Futures project: Towards Safe Smart Construction (VF 2020-0315), Swedish research centre of eXcellence in PRoduction RESearch (XPRES), China Scholarship Council (CSC 202308430011).</p

Between freedom and trap : A qualitative study on young adults attitudes towards BNPL

Denna studie syftar till att utforska och beskriva unga vuxna konsumenters inställning till och användning av Buy Now, Pay Later (BNPL)-tjänster med fokus på hur BNPL integreras i deras köpprocess samt vilka beteendemässiga och tekniska faktorer som formar deras användarbeteenden. Genom en kvalitativ forskningsansats samlades data in via åtta semistrukturerade intervjuer som analyserades med en tematisk metod och tolkades genom teorier som Köpbeslutsprocessen, Prospect Theory samt Technology Acceptance Model (TAM). Studiens resultat pekar på tre huvudteman: de bakomliggande drivkrafterna för BNPL-användning, den dubbla naturen hos BNPL:s effekt på köpbeteende och ekonomisk ambivalens, samt användarnas medvetenhet och strategier för att hantera tjänsterna. Slutsatsen är att unga vuxnas relation till BNPL är komplex och präglad av en kontinuerlig förhandling mellan omedelbar nytta och framtida risk. Förståelsen för interaktionen mellan tekniska, psykologiska och beteendemässiga faktorer är avgörande. This study aims to explore and describe young adult consumers attitudes towards and use of Buy Now, Pay Later (BNPL) services in Sweden, focusing on how BNPL is integrated into their purchasing process and which behavioral and technological factors shape their user behaviors. Through a qualitative research approach, data were collected via eight semi-structured interviews, which were analyzed using a thematic method inspired by Braun and Clarke and interpreted through theories such as the Consumer Decision Process, Prospect Theory, and the Technology Acceptance Model (TAM). The study's results point to three main themes: the underlying drivers for BNPL use, the dual nature of BNPL's effect on purchasing behavior and economic ambivalence, and users' awareness and strategies for managing the services. The conclusion is that young adults' relationship with BNPL is complex and characterized by a continuous negotiation between immediate benefits and future risks. Understanding the interaction between technological, psychological, and behavioral factors is crucial

AR-aided robot programming

In the current industrial revolution, intelligent automation has become more important than ever, with robotics being one of its central pillars. Despite becoming more common and experiencing an increase in the number of installations, robots still present several challenges to implement. One of the biggest ones is programming them, as it requires extensive training, knowledge, and skills. Even then, it is still a time-consuming process. For those reasons, this thesis seeks to simplify robot programming by using Augmented Reality (AR) technology. For this purpose, a system capable of generating box-packing programs without the need to write a line of code was generated. In it, people from different backgrounds can fully develop paths to pack several objects just by selecting the box layout and the product’s sources in the User Interface (UI). Nevertheless, to allow for more control over the paths generated, the system incorporates 3 operating modes. In the most advanced, manual program development is also allowed by adding and modifying the path’s targets. To validate the system’s results, two experiments were conducted: one to test the system’s functionality and the other to measure its complexity, while also comparing it to commercially available software. Finally, the limitations, results, and potential of the system are discussed alongside its sustainability impact.Det finns övrigt digitalt material (t.ex. film-, bild- eller ljudfiler) eller modeller/artefakter tillhörande examensarbetet som ska skickas till arkivet.There are other digital material (eg film, image or audio files) or models/artifacts that belongs to the thesis and need to be archived.</p

BankID and LSS : Who gets to participate in the digital society?

Syftet med denna studie är att undersöka vilka tekniska, juridiska och praktiska hinder som finns för personer som omfattas av LSS (Lagen om stöd och service till vissa funktionshindrade) att använda BankID, samt vilka konsekvenser detta får i deras vardag. Studien bygger på en kvalitativ metod och semistrukturerade intervjuer med personer som arbetar på LSS-boende och andra yrkesroller som har insyn i hur personer med LSS påverkas av användandet och tillgången till digitala samhällstjänster. Analysen av intervjuerna gjordes med hjälp av en tematisk analys, där teman formulerade utifrån intervjuguiden låg till grund för hur materialet sorterades och tolkades. Resultatet visar att brist på teknisk utrustning, varierande nivå av digital kompetens och behov av stöd utgör hinder för att använda BankID. Det framkom också att förvaltarskap skapar begränsningar för att få ett BankID utfärdat av banken. Dessa hinder leder till att individens självständighet begränsas, beroendet av andra ökar och svårigheter att utföra dagliga ärenden som kräver e-legitimation. Slutsatsen är att BankID är en nödvändighet för digital inkludering, men att tillgången till tjänsten är ojämlik och i vissa fall diskriminerande. Studien visar att det finns ett behov av att utveckla inkluderande lösningar för digital identifiering som är tillgängliga för alla, inklusive personer med funktionsnedsättningar och deras ställföreträdare

Metagenomic nanopore sequencing using MinION to identify bacterial species and genes conferring antimicrobial resistance for early sepsis diagnosis using spiked human blood samples

Sepsis is one of the life-threatening illnesses defined by tissue damage and organ failure caused by a dysregulated host response to infection. Blood culture is the golden standard and the first-line tool for detecting infections. It takes several days to identify pathogens, their sensitivity, and resistance to antibiotics. Early diagnosis of sepsis is thereby crucial to improving the patient's life. This study evaluates metagenomic sequencing using MinION and Flongle flow cells to detect bacterial species and antibiotic resistance genes. The DNA was extracted from the spiked whole human blood from a healthy individual with microbial DNA. This project focused on evaluation of the amount of spike-in to be used in the whole human blood, bacterial identification, and the detection of antimicrobial genes that confer antibiotic resistance. The obtained data from the nanopore sequencing was analysed using EPI2ME. The further analysis was performed using the BV-BRC taxonomic classification and metagenomic read mapping. The higher DNA concentration and consistent absorbance values were obtained from both DNA extraction kits. The results from nanopore sequencing showed the difference in classified reads and average sequence length depending on the DNA extraction kit as well as the flow cell used. The difference in the bacterial identification and antimicrobial genes identification could also be seen between the flow cells used. The results indicated that nanopore sequencing with the MinION flow cell could be more valuable in the early diagnosis of sepsis, but further research is required to make it more efficient and faster for sepsis treatment. Improving the detection of gram-positive bacteria and optimizing DNA extraction and nanopore sequencing protocols is needed for rapid and accurate identification of pathogens in the early stages of sepsis

Forecasting of sick leave : Predictive analytics as decision support in municipal health and social care

Sjukfrånvaro är och har länge varit ett stort problem för vårdrelaterade yrkesgrupper. Den höga sjukfrånvaron beror på ett komplext samspel av individuella och organisatoriska faktorer såsom hög arbetsbelastning, oregelbundna arbetstider, arbetsmiljö och arbetsrelaterad stress. Detta leder till att svensk sjukvård begränsas i sitt vårdgivande uppdrag i och med att personalbortfallet är högt. Sjukfrånvaro utgör därför en central utmaning för det svenska hälso- och sjukvårdssystemet. Denna studie tillämpar en kvantitativ forskningsansats med en experimentell design i syftet av att undersöka om prediktiva modeller kan utgöra ett tillförlitligt beslutsstöd för den kommunala hälso- och sjukvårdssektorn, och samtidigt undersöka vilken modell som bäst kan prognostisera sjukfrånvaro. Två multiklassificeringsmodeller har utvecklats och tränats på ett omfattande dataunderlag: Random Forest och XGBoost. Resultatet indikerar en försiktig optimism för tillämpning av prediktiva modeller i den kommunala hälso- och sjukvårdssektorn. XGBoost uppvisade bäst övergripande prestanda, medan Random Forest gav ett mer balanserat resultat.Prediktiv analys som beslutsstöd i kommunal hälso- och sjukvård</p

Evaluating hyperparameter optimization on the generalization of deep reinforcement learning algorithms

Deep Reinforcement Learning (DRL) is a branch of Artificial Intelligence (AI) focused on developing decision-making systems that learn through interaction with their environment. A central challenge in DRL is generalization—the ability of trained models to perform well in previously unseen environments. This study aims to evaluate the impact of hyperparameter optimization (HPO) on the generalization capabilities of two popular DRL algorithms: Proximal Policy Optimization (PPO) and Soft Actor-Critic (SAC). HPO, typically used to improve task-specific performance by finding the optimal hyperparameters (HPs), is investigated here as a potential method to enhance generalization. Experiments were conducted to compare the performance of PPO and SAC with and without HPO across varied environments. Results indicate that SAC benefits from HPO, whereas PPO performs better with default settings. These findings suggest that the effectiveness of HP tuning in DRL is highly context-dependent, influenced by both the choice of algorithm and the characteristics of the environment

Towards Zero Defect Manufacturing : Computer Vision-Enhanced Mixed Reality for Quality Inspection

In pursuing Zero Defect Manufacturing (ZDM), this study explores an innovative quality inspection method that combines computer vision with mixed reality for real-time error detection. Aligned with Industry 5.0, the proposed solution not only enhances operational efficiency in manufacturing but also promotes worker well-being by simplifying and automating the inspection and error detection process—a task that is usually demanding both mentally and physically for human operators. This approach enables operators to view and interact with accurate inspection data directly overlaid on real-world objects, improving their ability to spot and correct defects immediately. A case study in electrical terminal assembly demonstrates how deep learning-powered object detection integrated with MR improves inspection accuracy and efficiency. This work represents a significant step forward in automated quality control, supporting ZDM’s goals for sustainable, high-precision, and human-centered manufacturing.CC BY-NC-ND 4.0Corresponding author:Tel.: +46-500-448000. E-mail address: [email protected] authors would like to thank the Knowledge Foundation (KKS), Sweden, for their financial support through the ACCURATE 4.0 project, under grant agreement No. 20200181. We also wish to extend our appreciation to the industrial partner of the project, Xylem Water Solutions Sweden AB. Their collaboration, expertise, and invaluable insights have significantly contributed to this study.Alt. ScopusID: 105009400603ACCURATE 4.

The importance of forecast uncertainty in understanding the Bullwhip effect

The Bullwhip Effect, the magnification of demand variability throughout the supply chain, poses a challenge to firms. Inaccurate forecasts increase it, with forecast errors translating into higher inventory costs at a local level and impacting other members of the supply chain, as their decisions are based on mis-estimated incoming orders. The conventional measure for the Bullwhip Effect does not reflect how forecast uncertainty evolves in the supply chain. A new metric is proposed that overcomes many of the limitations of the Bullwhip Ratio: the Ratio of Forecast Uncertainty. It benchmarks the upstream forecast errors to the downstream's. An inventory simulation is deployed to study the properties and usefulness of this measure. It connects to inventory costs at the upstream level and holds more explanatory power than the standard Bullwhip Ratio and the complementary Net Stock Amplification. Managers can use it to better understand the upstream impact of the forecasting process.CC BY-NC-ND 4.0Published online: 09 Jul 2025Taylor &amp; Francis Group an informa businessContact: Patrick Saoud [email protected] Centre for Marketing Analytics and Forecasting, Department of Management Science, Lancaster University Management School, Lancaster LA1 4YX, UK</p