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Stormwater tree pits with storage elements enable the irrigation of urban trees and can potentially act as decentralized rainwater retention basins. This paper mainly focuses on analyzing this potential. Field tests were conducted to investigate the irrigation behavior and the storage effect of a storm water tree pit system using Perl hoses as irrigation elements over a period of two years.
The rainfall, storage volumes, and soil moisture within the employed planting pit were measured.
With the help of system modeling, the retention ability of the storm water tree pit system was analyzed. The available storage volume was sufficient to irrigate trees for several days. During the measurement period, about 15% of the inflowing rainwater was fed to the root zone of the tree. With practical storage volumes of 200 to 300 m3/ha, a remarkable amount of water from heavy rainfall could be completely stored, thus significantly reducing the risk of flooding. The retention effect and irrigation behavior largely depend on the soil conditions and the technical possibilities of the equipment supplying the root area (in this case, Perl hoses). Further investigations are required to determine the influence on the growth conditions of trees and optimize of the system for discharge into the root zone.
The extended quasiparticle picture is adapted to non-Fermi systems by suggesting a Pad´e approximation which interpolates between the known small scattering-rate expansion and the deviation from the Fermi energy. The first two energy-weighted sum rules are shown to be fulfilled independent of the interpolating function for any selfenergy. For various models of one-dimensional Fermions scattering with impurities the quality of the Pad´e approximation for the spectral function is demonstrated and the reduced density matrix or momentum distribution is reproduced not possessing a jump at the Fermi energy. Though the two-fold expansion is necessary to realize the spectral function and reduced density, the extended quasiparticle approximation itself is sufficient for the description of transport properties due to cancellation of divergent terms under integration.
The T-matrix approximation leads to the delay time as the time two particles spend in a correlated state. This contributes to the reduced density matrix and to an additional part in the conductivity which is presented at zero and finite temperatures. Besides a localization at certain impurity concentrations, the conductivity shows a maximum at small temperatures interpreted as onset of superconducting behaviour triggered by impurities. The Tan contact reveals the same universal behaviour as known from electron-electron scattering.
Purpose
The purpose of this paper is to investigate the relationships between technology orientations and export performance of small and medium-sized enterprises (SMEs).
Design/methodology/approach
A quantitative research design was adopted for this study. The paper formulates hypotheses from the literature review. These hypotheses are tested using structural equation modeling with data collected from 231 SMEs in Uganda. Data were analyzed using SPSS version 23 and AMOS.
Findings
The findings of this study showed technology orientation has a positive and significant relationship with the performance of Ugandan SMEs and that supply chain agility moderates technology orientation and export performance.
Research limitations/implications
The study discusses the findings, advances limitations and managerial implications. It also suggests future research avenues. It proposes some recommendations to help Ugandan SMEs to form flexible supply chains, use the latest technology and create strong relationship ties with their partners in the supply chain.
Practical implications
The study suggests that managers of Ugandan SMEs should use the latest technology in production, marketing, logistics and supply chain management which will enable them to respond quickly to customer tastes and preferences leading to higher levels of export performance.
Originality/value
This study contributes to the literature on strategic management showing the reliability of scales used and the confirmatory of the factor structure. This study shows that in strategic management technology, orientation is critical in increasing export performance. This study has extended the resource-based view (RBV) and dynamic capabilities theories.
From Surviving to Living (on): A Grounded Theory Study on Coping in People with Pancreatic Cancer
(2023)
Non-communicable diseases (NCD) are associated with high costs for healthcare systems. We evaluated changes in total costs, comprising direct and indirect costs, due to a 24-month non-randomized, controlled lifestyle intervention trial with six measurement time points aiming to improve the risk profile for NCDs. Overall, 187 individuals from the general population aged ≥18 years were assigned to either the intervention group (IG; n = 112), receiving a 10-week intensive lifestyle intervention focusing on a healthy, plant-based diet; physical activity; stress management; and community support, followed by a 22-month follow-up phase including monthly seminars, or a control group (CG; n = 75) without intervention. The complete data sets of 118 participants (IG: n = 79; CG: n = 39) were analyzed. At baseline, total costs per person amounted to 67.80 ± 69.17 EUR in the IG and 48.73 ± 54.41 EUR in the CG per week. The reduction in total costs was significantly greater in the IG compared to the CG after 10 weeks (p = 0.012) and 6 months (p = 0.004), whereas direct costs differed significantly after 10 weeks (p = 0.017), 6 months (p = 0.041) and 12 months (p = 0.012) between the groups. The HLCP-2 was able to reduce health-related economic costs, primarily due to the reduction in direct costs.
A communication over an Internet Protocol (IP) based network fails if an endpoint sends packets that are too big to reach their destination and if the sender is unable to detect that. The node on the path that drops these packets should respond with a Packet Too Big (PTB) message. However, multiple scenarios exist in which the sender will not receive a PTB message. Even if it does, it refrains from using the information in case it suspects that a potential attacker forged the message. In particular, we are not aware of any implementation of the secure transport protocol QUIC (e.g., used by HTTP/3) that processes PTB messages. In this paper, we present a novel parameterizable PTB detection algorithm for reliable transport protocols that does not depend on PTB messages. We further describe how to integrate our algorithm into QUIC, present results from an evaluation using the algorithm within a QUIC simulation model and, based on these results, suggest concrete parameter values.
The use of computational modeling and simulation (CMS) as a tool for gaining insight into the technical performance and safety of medical devices has emerged continuously over the past years. However, to rely on information and decisions derived from model predictions, it is essential to establish model credibility for the specific context of use. Limited regulatory requirements and lack of consensus on the level of verification and validation activities required result in rare use of CMS as a source of evidence in the medical device approval process. The American Society of Mechanical Engineers (ASME) developed a risk-informed framework to establish appropriate credibility requirements of a computational model: the ASME V&V 40?2018 standard. This paper aims to outline the concepts of this standard and to demonstrate its application using an example from the orthotics field. The necessary steps to establish model credibility for a custom?made 3D printed wrist hand orthosis (WHO) are presented. It is shown that the credibility requirements of each verification and validation activity depend on model risk by applying two different contexts of use to the same computational model.
Objectives: In recent years, the European Union has revised its regulatory framework for medical devices, primarily to improve patient safety and public health. The Medical Device Regulation (MDR) is fully applicable since May 2021, strengthening the requirements for all stakeholders. As a result, many companies are facing enormous challenges. The aim of this study was to assess the impact of the MDR on the orthopaedic aids industry.
Methods: Two surveys were conducted: one shortly before the MDR became applicable (146 respondents) and a second survey almost two years later (233 respondents).
Results: Both surveys revealed that all businesses in the orthopaedic aids sector, regardless of size, have difficulty implementing the MDR. Key challenges include additional workload for technical documentation, increased resource expenditure and cost, and lack of clarity regarding the new requirements. Many companies are downsizing their product portfolio, resulting in potential supply shortages and a loss of competitive advantage and innovation for the medical device industry in Europe.
Conclusions: The full extent of the MDR’s impact on clinical practice is still unclear. However, many companies lack the necessary resources. The MDR can potentially be a bottleneck in the availability of medical devices.
This review paper presents a short overview of current power system modelling tools especially used for analysing energy and electricity systems for the supply and demand sector. The main focus of this review lies on open source tools and models which are written and used in the programming language “Python”. The modelling tools are represented in a comprehensive table with key information. Five modelling tools with an open source license can be filtered out. The modelling tool PyPSA can be considered as a high performing tool especially as the gap between power system analysis tool (PSAT) and energy system modelling tool.
This review is about where and which tidal power systems are currently deployed. It starts with an insight into the variety of different tidal power systems. With the help of a list from the European Marine Energy Center about currently used systems for tidal power plants, it quickly becomes apparent that two systems stand out. These are the vertical and horizontal turbines. The latter are particularly common, as they are used for both tidal stream and tidal range power plants. Determining the regions with high potential for tidal power is not always easy due to the many influencing factors. Influencing factors are, for example form and conditions of the seabed, topographical features of the coast or currents in the sea [1]. Therefore, each region must be considered separately. n this paper the focus is on the UK, the literature shows that the coastal regions around the UK provide about 50 TWh/year of the European tidal power potential. This is due to the location between the oceans and the geological conditions, which act as a channel for the tides. The two areas with high potential where planning
and construction of tidal power plants is currently underway are in the north of Scotland and in the southwest of England in the Bristol Channel.
The use of wind power is rapidly expanding worldwide. It is important to examine the impact of wind turbines on the environment to see if they provide a net benefit and to identify potential for improving. Therefore life cycle assessments (LCA) of different wind turbine types are compared in this short review. The results are then shown side by side in tables for comparison. Overall the LCAs show that wind turbines compensate the required energy and emitted pollutants after approx. 6-16 months. The energy payback period (EPP) for 2 MW onshore wind turbines remained roughly the same since 2009 with approximately 7 months. Onshore wind turbines have a higher impact due to emissions but a shorter EPP than offshore wind turbines. The estimated service life of 20 years should be maximized to ensure a high energy yield ratio. The biggest impact on the environment results from the processes to provide the building material e.g. steel and cement. That impact could be reduced by 20 % if recycled steel would be used. It is shown that wind power is one of the cleanest energy sources. But further investigations in material processing and recycling are important to improve the eco-balance of wind turbines.
For the increasingly important storage of renewably generated electricity, this review explains the construction of a surface and underground pumped storage
power plant. The problems for the construction of an underground pumped storage power plant are further listed. These are geological, environmental and
economic problems as well as a low acceptance by the population. The geological problems are concerns about leaching of minerals and heavy metals as well as the statics of the cavities. Mining companies in Germany are obligated to renaturalize the landscape areas again, which could be realised by a lake. Furthermore, care must be taken to ensure that the mine water does not come into contact with the groundwater. According to a survey by RISP on the subsequent use of the mine areas for an underground pumped
storage power plant, the acceptance of the population is over 70 percent. The economic consideration concludes that the arbitrage profit for a difference between off-peak and peak of 10 €/MWh is about 2.7 M€/a and for 100 €/MWh about 27.3 M€/a. With investment costs of about 630 M€, despite the assumption of 100 €/MWh, more than 20 years are needed for an underground pumped storage power plant to be amortized. The acceptance could be increased by creating a lake as a recreation area as well as being used as an upper storage reservoir. Thus, the cost of renaturation decrease when combined with the creation of the storage basin. The problem of ground conditions can be solved by creating new cavities by means of tunnel boring at an inclination. For static safety as well as against leaching of minerals and heavy metals, the cavity walls can be sealed with reinforced concrete. The technology of underground pumped storage power plants can be used for better utilisation of renewable energies. This is especially in flat and densely populated regions a possibility to store energy, because the main part of the power plant is underground.
The Educational Journal of Renewable Energy Short Reviews (EduJRESR, formally published as `EGU Journal of Renewable Energy Short Reviews') is a teaching project rather than a regular scientific journal. To publish in this journal, it is a premise to take part in the master course wind power, hydro power and biomass usage at the department of Energy, Building Services and Environmental Engineering of the Münster University of Applied Sciences.
Students receive an equivalent of 2.5 credit points (European Credit Transfer and Accumulation System - ECTS) for their engagement in the course and for publishing a short review article of at most 3000 words in this periodical. The publication process closely mimics the typical publication procedure of a regular journal. The peer-review process, however, is conducted within the group of course-participants.
Although being just an exercise, we think that publishing the outcome of this course in a citable manner is not only promoting the motivation of our students, but may also be a helpful source of introductory information for researchers and practitioners in the field of renewable energies. We encourage students to write their articles in English, but this is not mandatory. The reader will thus find a few articles in German language. To further encourage students practicing English writing, perfect grammar is not part of the assessment.
We especially thank our students for working with LaTeX on Overleaf, although LaTeX is new to some of them. In this way, the editorial workload was reduced to a minimum. We also thank our students for sharing their work under the creative commons attribution licence (CC-BY). We appreciate their contribution to scientific information, being available to every person of the world, almost without barriers. We also thank the corresponding authors and publishers of the cited work, for granting permission to reuse graphics free of charge. All other figures had to be replaced or removed prior to publication.
This report examines the strength of young and early age concrete that has been systematically exposed to horizontal, sinusoidal vibrations with varying vibration parameters. Specimens were subjected to vibrations of predefined vibration times (4–14 h) and the compressive strength was determined after a period of 28 days. It was found that the different parameters have no critical influence on compressive strength and that vibration prior to initial setting of the concrete can increase its strength. Additional information to examine the reasons for this increase was obtained by further investigations (nuclear magnetic resonance, x-ray diffraction, and thermogravimetric analysis).
Purpose: This study investigated the effectiveness of the stuttering modification intervention Kinder Dürfen Stottern (KIDS) in school-age children who stutter.
Method: Seventy-three children who stutter were included in this multicenter, two-group parallel, randomized, wait-list controlled trial with a follow-up of 12 months. Children aged 7–11 years were recruited from 34 centers for speech therapy and randomized to either the immediate-treatment group or the 3 months delayed-treatment group. KIDS was provided by 26 clinicians who followed a treatment manual. Although the primary outcome measure was the impact of stuttering (Overall Assessment of the Speaker’s Experience of Stuttering–School-Age [OASES-S]), the secondary outcomes included objective and subjective data on stuttering severity.
Results: At 3 months postrandomization, the mean score changes of the OASESS differed significantly between the experimental (n = 33) and control group (n = 29; p = .026). Furthermore, treatment outcomes up to 12 months were analyzed (n = 59), indicating large effects of time on the OASES-S score (p < .001, partial η2 = .324). This was paralleled by significant improvements in parental ratings and objective ratings (stuttering severity, frequency, and physical concomitants).
Conclusions: The significant short-term treatment effects in the OASES-S are in line with the (initial) focus of KIDS on cognitive and affective aspects of stuttering.
Over 12 months, these changes were maintained and accompanied by
behavioral improvements. The results suggest that individual treatment with KIDS is an adequate treatment option for this age group.
The Spreadsheet Energy System Model Generator (SESMG) is a tool for modeling and optimizing energy systems with a focus on urban systems. The SESMG is easily accessible as it comes with a browser-based graphical user interface, spreadsheets to provide data entry, and detailed documentation on how to use it. Programming skills are not required for the installation or application of the tool. The SESMG includes advanced modeling features such as the application of the multi-energy system (MES) approach, multi-objective optimization, model-based methods for reducing computational requirements, and automated conceptualization and result processing of urban energy systems with high spatial resolution. Due to its accessibility and the applied modeling methods, urban energy systems can be modeled and optimized with comparatively low effort.
This study investigated the ability of electrically conductive carbon rovings to detect cracks in textile-reinforced concrete (TRC) structures. The key innovation lies in the integration of carbon rovings into the reinforcing textile, which not only contributes to the mechanical properties of the concrete structure but also eliminates the need for an additional sensory system, such as strain gauges, to monitor the structural health. Carbon rovings are integrated into a grid-like textile reinforcement that differs in binding type and dispersion concentration of the styrene butadiene rubber (SBR) coating. Ninety final samples were subjected to a four-point bending test in which the electrical changes of the carbon rovings were measured simultaneously to capture the strain. The mechanical results show that the SBR50-coated TRC samples with circular and elliptical cross-sectional shape achieved, with 1.55 kN, the highest bending tensile strength, which is also captured with a value of 0.65 Ω by the electrical impedance monitoring. The elongation and fracture of the rovings have a significant effect on the impedance mainly due to electrical resistance change. A correlation was found between the impedance change, binding type and coating. This suggests that the elongation and fracture mechanisms are affected by the number of outer and inner filaments, as well as the coating.
This study explores the intriguing relationship between personality traits, self-rated fitness (SRF), and physical activity (PA) variables among German university students (N = 4244) and sheds light on the impact of personality on adherence to PA guidelines. Employing an online cross-sectional study, the short-form of the Big Five Inventory-2 assessed five domains of personality traits (Extraversion, Negative Emotionality, Agreeableness, conscientiousness, and Open-Mindedness). PA, including sitting time, was assessed using the International Physical Activity Questionnaire (short-form). SRF and muscle-strengthening activities (MSA) were assessed with one item each. Multiple linear and logistic regression analyses examined associations of individual personality trait domains and all domains combined with SFR, PA variables, and adherence to PA guidelines, controlling for sociodemographic, behavioral, and (mental) health covariates. Most reliably, Extraversion and Conscientiousness revealed positive associations with PA variables, while Negative Emotionality yielded inverse relationships with PA variables. For instance, each unit increase in Extraversion corresponded to an additional 17 min of weekly MSA. On the contrary, daily sitting time was unrelated to personality. Of note, high Open-Mindedness was associated with lower odds for adhering to current PA guidelines. The findings have implications for developing targeted interventions that promote a physically active lifestyle and support students’ well-being and academic success.
Oxidative stress plays a critical role in the pathogenesis of chronic diseases. Therefore, improvement of oxidative stress status through lifestyle intervention can play a vital role in preventing and treating chronic diseases. This systematic review aims to provide an overview of articles published in the last decade examining the association between lifestyle intervention and oxidative stress biomarkers in the context of non-communicable diseases. The electronic databases PubMed and Web of Science were searched for relevant studies, following the PRISMA (Preferred Reporting of Systematic Reviews and Meta-Analyses) guidelines. This systematic review focused on the four important oxidative stress biomarkers; glutathione (GSH), superoxide dismutase (SOD), catalase, and malondialdehyde. 671 articles were identified, of which nine met the inclusion criteria. A trend emerged, showing that lifestyle modifications that focus on diet and physical health can improve oxidative stress in the form of an increase in superoxide dismutase and CAT levels and a decrease in Malondialdehyde levels in participants with non-communicable diseases (NCDs), GSH levels were not affected. However, the results are difficult to compare because of the heterogeneity of the methods of the biomarkers studied. Our review indicates that oxidative stress can be influenced by lifestyle modifications and may be an effective tool for the prevention and management of non-communicable diseases. This review also elucidated the importance of analyzing multiple oxidative stress biomarkers to evaluate oxidative stress, it further highlights the need to conduct long-term lifestyle intervention studies on oxidative stress biomarkers to understand the connection between oxidative stress biomarkers, NCDs and Lifestyle intervention.
The construction sector is one of the largest consumers of raw materials and energy, as well as a producer of CO2 in the European Union. To reduce environmental pollution and to preserve raw materials and energy, resource-efficient building elements must be designed. Even if laws demand resource-efficient product design in the building sector, there is no independent evaluation system for the resource efficiency of building elements (e.g., walls, roofs, floors). Such an evaluation should take the whole life cycle into account. The measurement of reusability and recyclability is therefore necessary. This article, therefore, describes the development of an evaluation system for reusability and recyclability to be included in resource efficiency assessment. Existing approaches and the special requirements of the building sector are considered. Finally, a practical example shows that the developed system is suitable for the assessment of reusability and recyclability. It can be used for the comparison of different construction methods or for the comparison of specific designs or products; thus, the evaluation system is helpful for architects as well as for product designers.