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Symmetry transformation methods are widely used in fluid flow problems. One such method is renormalization group analysis. Renormalization group methods are used to develop a macroscopic turbulence model for non-Newtonian fluids (Oldroyd-B type). This model accounts for the large-distance and large-time behavior of velocity correlations generated by the momentum equation for a randomly stirred, incompressible flow and does not account for empirical constants. The aim of this mathematical study was to develop a k -ε RNG turbulence model for non-Newtonian fluids (Oldroyd-B type). For the first time, using the renormalization procedure, the transport equations for the large-scale modes and expressions for effective transport coefficients are obtained. Expressions for the renormalized turbulent viscosity are also derived. This model explains the phenomenon of the abrupt growth of the irregularity of velocity at low values of the Reynolds number.
Crises appear to be occurring with increased frequency, whether provoked directly by human actions or through indirect causes such as resource scarcity or natural disasters. Crisis management strategies are frequently implemented with the aim of mitigating the immediate impacts of these crises. Nevertheless, it is critical to also consider the long-term consequences of such strategies. This study investigates both the short- and long-term effects of various crisis management strategies during a financial crisis in relation to the energy transition. An agent-based model of the German electricity sector is developed to analyze the effects of different strategies. The findings suggest that a reduction in electricity demand by 10% achieves the most favorable outcomes, decreasing short-term electricity costs by 11% and long-term carbon dioxide emissions by 9%.
The surge in cross-border banking prior to the 2007 / 08 global financial crisis took place not only in the interbank market but also in the retail market, e.g. between banks and their private customers abroad. Cross-border retail activities of banks now account for a substantial share of total international activities. Despite its rising importance, we are just starting to understand the role of cross-border retail banking for globalization and stability. In this study, we assess this less known part of financial globalization by reviewing the development and structure of cross-border banking, identifying the factors that drive retail customers across borders and assessing the impact of financial crises on global retail banking. (F3, F15, F65, G01, G15, G21)
As design thinking becomes more and more important in higher education, we need to think about ways to enable educators and students to learn about the concepts and apply them to their own projects. One approach is to create hybrid learning spaces with tools that support design thinking and offer affordances for the various methods, ways of working and thinking. Hybridity dissolves existing dichotomies such as physical-digital, formal-informal, learning-teaching and individual-collective. This article introduces design principles and patterns to develop such spaces for university campuses. We will describe how we identified, applied and tested them. Based on these findings we can provide recommendations for planning new hybrid spaces for design thinking at other universities.
The Method Radar: A Way to Organize Methods for Technology Development with Participation in Mind
(2023)
Identifying appropriate methods for any process, such as uncovering needs of juveniles in social welfare or designing interactive systems, requires intensive research and generally using a categorization system that brings methods in a systematic order. These taxonomy systems are heavily responsible for the later method usage and start the thinking process for researchers and practitioners alike in a specific direction. So making participation visible in such taxonomy systems directly affects the later method usage and makes participation more visible and easier to use. This article presents the Method Radar, a visualized categorization of methods with a focus on participation using the ladder of participation, that makes participation visible right at the beginning of any method selection. The Method Radar builds on the radar representation established in the technology sector, which allows a multi-dimensional classification. In addition, an implementation and systematic process for categorizing these methods are presented. It can be used for any form of method categorization in which participation is supposed to be thought of.
Informal social networks and especially advice networks are a key subject of organizational sociological research. The formation of these networks has so far been explained on the basis of universal tie-formation mechanisms. However, recent conceptual contributions suggest that tie formation practices follow cultural rules that may vary across social contexts. In our paper, we substantiate this argument empirically. Based on rich qualitative data, we compare advice tie formation (a) between two entrepreneurial communities and (b) between three research and development departments of large enterprises. We show that both impact and configuration of tie formation mechanisms systematically differ between comparable contexts. Building on our findings, we finally formulate propositions describing which advice network structures can be expected in specific cultures.
Background:Perceived safety has received attention in the digital transformation of healthcare. However, the impact of perceived safety on the future of digital transformation has not been fully elucidated.
Aim: To investigate perceived safety in the context of the digital transformation of healthcare while considering relevant needs, influencing factors and impacts, including crisis events, to provide recommendations for action based on a participatory, multiperspective, strategic 5-year foresight viewpoint.
Methods: A strategic foresight study is conducted via a participatory mixed-methods design to understand the present related factors that are likely to be relevant to future developments in the digital transformation of healthcare.
Results: We observed that feeling safe plays a complex role in the digital transformation of healthcare. How perceived safety is considered has and will continue to impact the individual, organisational and system levels. Regarding a potential crisis event, controversial consequences have been observed. At its core, digital (health) literacy related to equity of access and human support is one of the crucial aspects in the context of perceived safety related to the successful implementation of digital technologies in healthcare.
Conclusions: The scenarios showed that a continuation of the current situation over the next 5 years may result in partly desirable and partly undesirable outcomes. Concrete key factors should be used in practice to support both education and healthcare quality development and research. The essence of the scenarios should serve as a starting point for research agenda setting and political decision-making in the future. However, additional research is needed to quantify the correlations among the relevant factors.
As part of the energy transition, near-Zero-Energy-Buildings use electric systems that reduce emissions and consumption. Nevertheless, the increased use of such systems comes with the E-waste challenge. Circular Economy concepts try to make more efficient use of these materials, but sustainable evaluations mainly focus on energy and emissions. The developed automated text analysis tool quantifies the appearance of circularity concepts in open-access literature about different stages of production, use, and end-of-life for heat pumps, Lithium-Ion batteries, photovoltaic modules, and inverters. The energy focus is corroborated in different amounts depending on the component and stage, and when circularity concepts appear, they are centred on waste and recycling. Numerical variables to model environmental impact available in open-access literature are limited, generalised, or present in a wide range. Access to product environmental specifications should be encouraged to ensure that energy transition is sustainable in all its dimensions.
A fiber-based linear optical coherence tomography (LOCT) system employing a cost-effective CMOS camera has previously demonstrated high-resolution imaging suitable for retinal screening, including glaucoma monitoring. However, the system’s imaging depth was constrained to approximately 400μm, insufficient for depth imaging of the optic nerve head (ONH), due to limitations imposed by the camera’s sensor size and pixel pitch. To overcome this limitation without replacing the economical and available sensor, we present a modification to the reference arm. By optimizing the utilization of the camera sensor’s vertical dimension, the system achieves an extended imaging depth, enabling the visualization of deeper tissue structures. Validation using an artificial eye model confirms that the modified LOCT system significantly enhances imaging depth while maintaining B-Scan quality. This advancement offers a cost-effective approach to extend the measurement range of LOCT systems, broadening their applicability in retinal imaging without altering the actual imaging sensor.
This paper presents a method for dynamically controlling the gaze movement of patients during ophthalmic examinations, specifically using infrared funduscopy and Optical Coherence Tomography (OCT) to gather retinal information essential for glaucoma screenings. By using the patient's natural eye movements, this system eliminates the need for traditional precise scanning mirrors used in conventional OCT devices, which typically direct the OCT laser beam across the retina to produce A-scans. In this approach, the OCT laser beam remains fixed while the patient is guided to follow a predetermined pattern on a display with their eyes. This method effectively uses the patient’s eye movements to replace the functionality of scanning mirrors. By tracking the position of the eye in real time, the system ensures that the specific areas of the retina are captured. This technique not only provides a cost-effective alternative to traditional OCT systems but also enhances patient comfort by involving them actively in the process, reducing the need to fixate on a single point. During the examination, the system evaluates each measurement point, and the scan patterns can be adjusted if necessary to ensure comprehensive diagnostic data acquisition. The resulting positions are assigned to the OCT A-scans. This allows the optic nerve B-scans typical for glaucoma examinations to be created in the evaluation. The system is characterized by the fact that it enables flexible adjustments to the imaging patterns in real-time, based on which areas of the eye have already been captured and which still require examination. The setup mainly uses commercially available components to create a cost-effective alternative to conventional, often price-intensive diagnostic devices. This method has the potential to be important not only for the improved diagnosis and monitoring of eye diseases, including glaucoma, but also offers prospects for wider application in preventive eye health care.