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On the consistency of dynamic wetting boundary conditions for the Navier–Stokes–Cahn–Hilliard equations
Full text linkWe investigate the limiting behavior of the Navier–Stokes–Cahn–Hilliard model for binary-fluid flows as the diffuse-interface thickness passes to zero, in the presence of fluid–fluid–solid contact lines. Allowing for motion of such contact lines relative to the solid substrate is required to adequately model multi-phase and multi-species fluid transport past and through solid media. Even though diffuse-interface models provide an inherent slip mechanism through the mobility-induced diffusion, this slip vanishes as the interface thickness and mobility parameter tend to zero in the so-called sharp-interface limit. The objective of this work is to present and analyze dynamic wetting and generalized Navier boundary conditions for diffuse-interface models that are consistent in the sharp-interface limit. We concentrate our analysis on the prototypical binary-fluid Couette-flow problems. To verify the consistency of the diffuse-interface model in the limit of vanishing interface thickness, we provide reference limit solutions of a corresponding sharp-interface model. For parameter values both at and away from the critical viscosity ratio, we present and compare the results of both the diffuse- and sharp-interface models. As a corollary of the close agreement between the diffuse-interface and sharp-interface results, the presented results can serve as a benchmark for future investigations.</p
Driving business performance through green procurement policy:The power of supply chain information sharing for robust supply chain
Full text linkFew researchers seek to understand how firms can drive business performance through green procurement policy. Fewer still embrace the power of supply chain information sharing for robust supply chain management. If this is so, then there is a cause for concern. Here, the researchers used SmartPLS4 for data analysis and model testing, utilizing the mediating effects of supply chain resilience and supply chain robustness in the relationship between green procurement policy and business performance. The researchers found a positive association between supply chain information sharing, entrepreneurial orientation proactiveness, and green procurement policy. The results signify that supply chain resilience and supply chain robustness mediate the constructive association between green procurement policy and business performance. Our findings have practical implications where firms can promote information flow, foster proactive entrepreneurship, and enhance supply chains’ resilience and robustness to support green procurement strategies. By integrating these insights into their strategy, businesses can gain a competitive advantage in the global market while fulfilling their regulatory requirements and stakeholder expectations. Our research is the first to examine the mediating role of supply chain resilience and supply chain robustness in ensuring the impact of green procurement policy on enhancing business performance.</p
Salient and subtle behaviors in social interaction:Investigating the social effects of virtual humans
No full textHumans’ nonverbal behaviors in social interaction, such as facial expressions, eye gaze, and even subtle cues such as pupil dilation, may have social effects. For example, they may be associated with higher trust by the interaction partner or may influence the interaction partner’s emotional responses. Moreover, anxiety in social situations may influence the expression and evaluation of behaviors, as well as emotional responses. Recent advances in technology enable people to interact with artificial agents such as virtual humans. In psychological research, virtual humans are beneficial for investigating social behaviors as they can balance experimental control and ecological validity. At the same time, a systematic investigation of virtual humans’ social effects can support their development, including applications aimed at reducing anxiety in social situations. Throughout three empirical studies, this dissertation investigates how salient and subtle behaviors in social interaction with virtual humans affect social evaluation and emotional responses, and whether anxiety in social situations influences these social effects. The results show that, first, virtual humans’ positive behaviors and pupil dilation mimicry (in modulation with eye contact) enhance social evaluations of virtual humans (Chapter 4 and 3), suggesting their potential for improving future applications of virtual humans. Importantly, it generalizes the social effects of pupil mimicry to a richer situation involving storytelling with virtual humans. Second, humans’ own behavior contributes to the social evaluation; mimicking smiles and making more eye contact enhances humans’ evaluation of the virtual humans (Chapter 2 and 3), generalizing their effects from human-human interaction to human-virtual human interaction, and may provide an alternative way to assess humans’ evaluation of virtual humans. Third, anxiety in social interaction moderates the social effects of virtual humans, but only when the situation implies higher social risks (Chapter 4), highlighting the importance of customizing social situations and measuring anxiety levels, especially in applications that aim to benefit people with social or public speaking anxiety. Collectively, this dissertation contributes to a more systematic investigation of the social effects of virtual agents, as well as the study of salient and subtle behaviors in social interaction in ways that balance ecological validity and experimental control
Endoscopic sleeve gastroplasty video assessment:Do technical features influence ESG integrity and weight loss at 6 and 12 months follow-up?
No full textBackground: Endoscopic Sleeve Gastroplasty (ESG) allows for gastric volume reduction and shortening leading to weight loss and resolution of obesity-related comorbidities. While position statements and recommendations are being developed, limited studies have explored how technique influences outcomes. Video-based assessment (VBA) of endoscopic and surgical procedures are increasingly being adopted to achieve a deeper understanding of procedures technical aspects. This study explores how ESG technical features and anatomical landmarks relate to outcomes, and to develop predictive models from them. Methods: Videos of ESG were collected, and an annotation manual was developed by an ESG expert, outlining technical and anatomical landmarks possibly influencing 6 and 12 month outcomes. Evaluated outcomes included technical (i.e., intact gastroplasty) and clinical (i.e., total and excess weight loss percentages) success. Two independent surgeons annotated the videos. Analysis of annotated features and of an engineered feature was performed; predictive regression models were developed. Pearson correlation and inter-rater reliability (IRR) of the annotations were evaluated. Results: Forty videos were annotated. The features “Bleeding,” “Hemicircumferential” suture pattern encircling 180° of the stomach’s incisura, “Suture number” and “Regular tubular ESG” configuration were analyzed. The engineered feature “Suture_Regular” defined by a combination of Regular tubular ESG” and “Suture number” was developed and analyzed. Predictive models were developed using progressively expanded feature sets in various combinations. XGBoost models demonstrated best performances across outcomes and timepoints, with R2 values of 0,74–0,87, depending on the outcome and timepoint evaluated. Single features exhibited limited predictive power. IRR varied by feature, with Cohen’s kappa ranging from slight to substantial. Conclusion: VBA can enhance the understanding of endoscopic techniques. Combinations of events occurring during ESG and technique-specific features can be used to predict technical and clinical success. Future studies should include multicentric data to enhance models generalizability. Automating feature recognition could enable real-time guidance and improve patient management.</p
Enfoldings of Redistribution, Recognition, and Misrecognition in Gentrifying Molenbeek, Brussels
Full text linkHow is gentrification experienced by people who cannot be clearly identified as “winners” or “losers” of the process? This article focuses on how homeowners experience gentrification in the Quartier Maritime in Molenbeek, Brussels, Belgium. Homeowners might benefit financially from gentrification, but they might at the same time oppose the process because of how it negatively affects their neighborhood and local inhabitants. This article employs a recognition-theoretical framework to study homeowners’ experiences of gentrification and argues that these should be understood as enfoldings of redistribution, recognition, and misrecognition. More precisely, misrecognition is the condition of possibility for the financial benefits and recognition as they materialized in their specific forms in the process of gentrification that we studied. Enfoldings of (mis)recognition thus present a useful concept to enrich our work on gentrification.</p
HCCE-CUNet Based Multi-Class Musculoskeletal Segmentation for Robotic Ultrasound System
No full textAccurate segmentation of musculoskeletal structures in ultrasound (US) images remains challenging due to speckle noise, multi-layer anatomical boundaries, and scanning variability. For the robotic ultrasound system, the quality of captured ultrasound images highly depends on the force and angle applied to the tissue during autonomous scanning. Consequently, how the autonomous scan is performed influences the subsequent image segmentation task. Particularly, segmentation algorithms for bone structures are relatively less affected by variations in applied force. In contrast, muscle segmentation remains particularly challenging due to tissue deformation caused by variations in applied force during robotic scanning. Existing algorithms typically focus on either bone or muscle, rather than addressing both structures simultaneously. To address those challenges, we proposed an autonomous robotic ultrasound system that integrates precise force control with a cascaded deep learning framework in this paper. Specifically, the Hybrid Channel and Coordinate Enhanced Cascaded U-Net (HCCE-CUNet) was designed to enable simultaneous segmentation of bone and multi-layer muscle structures with improved accuracy. Experimental evaluations on two customized forearm phantoms demonstrated the system’s reliability, achieving a root-mean-square error in force tracking below 0.14N, and showed significant segmentation improvements, with Dice coefficients of 0.8915 (single-layer phantom) and 0.9175 (multi-layer phantom). The proposed segmentation method extends the image processing capability of the robotic ultrasound to deal with hard tissues (i.e. bones) and multiple muscles simultaneously. In the future, it could have great potential to provide a reliable solution for operator-independent musculoskeletal diagnostics and interventions.</p
Highly Reactive Atomic Hydrogen as an Alternative Reactant for Atomic Layer Deposition of Platinum Using MeCpPtMe<sub>3</sub>
No full textAtomic layer deposition (ALD) of platinum (Pt) has gained significant interest in the recent years due to its capability of depositing various Pt nanostructures for applications in different fields, such as Pt nanoparticles (NPs) for catalytic reactions and energy devices and Pt thin films for microelectronic technology. Among various developed processes, Pt ALD using MeCpPtMe3as the precursor has been most popularly employed owing to the high reactivity, volatility, and thermal stability of the precursor, which enable controlled deposition of Pt nanostructures in a broad range of temperatures. Typical MeCpPtMe3-based Pt ALD processes use O2and H2as the coreactants. In this study, we explore atomic hydrogen as an alternative and reveal its exceptional reactivity that outperforms H2and O2. Specifically, atomic hydrogen enables the deposition of highly dispersed Pt NPs with narrow particle size distributions (i.e., standard deviation <0.3 nm) on various oxide surfaces, including TiO2, SiO2, CeO2and V2O5, which is unattainable with H2under identical experimental conditions. In addition, it facilitates the deposition of Pt NPs with improved size uniformity and accelerates the closure of Pt films compared to ALD processes using O2as the coreactant. The results demonstrate a significant potential of atomic hydrogen as a highly effective coreactant for ALD of Pt NPs and thin films.</p
Consumer responses to privacy invasion:The role of regulatory environments and social expectations
No full textPurposeThis study examines how regulatory environment and monetary reward influence consumer perceptions of a privacy invasion from a new or unknown brand.Design/methodology/approachThe study employs a 2 × 2 × 2 factorial design simulation, manipulating invasion severity and monetary reward to measure brand attitude and perceived invasion of privacy. It involves participants from the US and Germany (N = 595) interacting with a fictitious company via their mobile devices. The simulation of privacy invasion is prompted by disinformation on data collection of the respondents' mobile devices.FindingsPerceptions of privacy invasion intensified as the severity of the invasion increased. Greater privacy violations, particularly when paired with lower compensation, led to more negative brand attitudes. When privacy invasions were minimal, US participants perceived them more strongly than their German counterparts, likely due to differences in regulatory trust. However, in cases of high privacy invasion, German participants adjusted their perceptions based on compensation size, with larger rewards mitigating their concerns. In contrast, US participants maintained consistently high perceptions of invasion, regardless of compensation, suggesting a different evaluative approach to privacy violations.Practical implicationsThe findings provide insights for marketers and policymakers on how different regulatory environments and incentives might affect consumer perceptions and attitudes toward privacy invasion, which could inform strategies for managing customer relations, compliance and consumer well-being.Originality/valueThe study extends privacy calculus theory by examining post-invasion attitudes and perceptions in combination with offered compensation. It also provides cross-national comparisons and explores the impact of regulatory differences, contributing novel empirical evidence to the field
Running.Christel: A Stochastic Hybrid Case-Study Optimizing Battery Pack Usage
No full textOver the last two decades, batteries have become essential components in many high-tech systems, enabling the storage of (electrical) energy for later use. However, the high costs and scarcity of the materials used for high-end batteries make their efficient use and dimensioning a crucial aspect in system design. Enabling such dimensioning requires accurate modeling of the battery behavior under realistic workload conditions. In this paper we use the Kinetic Battery Model (KiBaM) to effectively capture key behavioral aspects of batteries at reasonable modeling costs. Also an accurate battery workload model is needed that describes the demand of energy over time; such workload models often include stochastic elements. Timed automata models have been used to evaluate battery lifetimes under (primarily) deterministic workloads for only small battery configurations. The previously proposed approach required a discretization that led to a computational error that could not be quantified in general. Instead, this paper adopts a stochastic hybrid modeling (SHM) approach to better capture battery dynamics as well as stochastic workloads. This paper, hence, presents an exploration of state-of-the-art SHM methods and tools for the analysis of battery systems under stochastic workloads, and an investigation of the advantages and disadvantages of these techniques
A Real-Time COPD Exacerbation Detection Algorithm Using multi-morbid symptom diaries:Insights from a Multi-Site Study
No full textChronic Obstructive Pulmonary Disease (COPD) is the fourth leading cause of death worldwide and is often accompanied by comorbidities. Patients, due to their health condition, may experience a rapid worsening of symptoms, defined as an exacerbation, which could lead to undesirable hospitalizations or emergency care. To lower this burden, early detection of symptoms as well as health monitoring are crucial. Data from routine clinical visits and follow-ups with the use of questionnaires and self-reported symptoms collected via a dedicated mobile app provide valuable insights that might enable a prompt identification of worsening health conditions. To this end, in this paper we propose a real-time exacerbation detection algorithm based on a paper version of a multimorbid symptom diary (the COPE-III study) developed in the scope of the RE-SAMPLE project. Results on its implementation and use in three hospitals across different countries in Europe are reported along with a discussion on its potential and challenges. Finally, we demonstrate that it detects exacerbation events that are associated with 46% of the emergency accesses and 32% of hospitalizations reported at GEM pilot site.</p