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Fraunhofer Institute for Structural Durability and System Reliability LBF starts project on using plastic recyclates in technical components. Plastic recyclates for sophisticated components Kunststoffrezyklate für anspruchsvolle Bauteile
No full textIW2IW3Ecological and social responsibility requires that we recycle plastic waste in order to make our consumption of resources more efficient and more sustainable. Moreover, legal provisions require that a part of the plastic recyclates is used in technical components. In the new project "Using Plastic Recyclates Reliably in Technical Components", the Fraunhofer Institute for Structural Durability and System Reliability LBF, together with partners, investigates the fundamental relationships between material flow, processing and long-term behavior in heavy-duty applications. The objective is to make products more sustainable and more durable and to use more plastic recyclates reliably in technical applications.766-
Who consumes and who conserves? Housing energy use and technology adoption across lifestyle groups
No full text178190Residential energy consumption is a major source of greenhouse gas (GHG) emissions and carbon inequalities, yet patterns of energy consumption and technology adoption vary substantially across social groups. This study examines how multidimensional lifestyle affiliations shape pro-environmental consumption patterns, including sufficiency, efficiency and consistency compatible practices. Drawing on a nationally representative survey carried out in Germany with a final sample size of 1817 respondents, we deploy latent class analysis to identify six distinct lifestyle types based on socio-economic, attitudinal and housing characteristics. We then assess how affiliation with these lifestyle types relates to differences in pro-environmental energy-related behaviours, household carbon footprints, and subjective well-being, using Welch ANOVA and Games-Howell post hoc tests. The findings show marked heterogeneity across lifestyle classes: high-income groups living in spacious dwellings tend to exhibit the highest per-capita energy use and carbon footprints, whereas affluent but younger and urban households display the lowest. Families show the highest uptake of energy-efficient and renewable technologies, while sufficiency-oriented practices appear to be driven by necessity rather than pro-environmental or sufficiency-oriented values. Subjective well-being also differs across lifestyle types, with high income not consistently associated with higher well-being, highlighting the potential role of values, life stage, and housing characteristics. Finally, we find that similar levels of energy consumption can result from distinct mechanisms - in some cases through reduced consumption, and in others through the adoption of efficiency or consistency technologies. These findings highlight the need for differentiated and equity-sensitive policy mixes, such as progressive pricing for high-consuming groups combined with rent-neutral efficiency standards and targeted support for structurally constrained households.6
Impact of the Blade Fillet Radius on the Aerodynamic Performance of an Unshrouded Centrifugal Compressor
No full textFillets are often neglected in the flow analysis of centrifugal compressors due to the assumption of having little influence on the flow field and the difficulties related to the grid generation. Existing studies have shown an impact on efficiency, pressure ratio and choke margin by including fillets in the flow simulation. The goal of the present work is to investigate the impact of the fillet radius on the aerodynamic performance in an unshrouded centrifugal compressor. A parametric study on the blade hub fillet radius is conducted using the "RadiVer" test geometry and steady state CFD analysis. By using common methods for grid generation of turbomachinery blade passages, which are stacking the surface grids for each blade section, 3D features, such as fillets, cannot be meshed properly. Therefore, a new topology for 3D multi-block structured grid generation of radial impeller blades including hub fillets is proposed. Transfinite interpolation is used to create the initial grid and elliptic smoothing is applied afterwards for removing grid folding and improving grid quality. From the results of the flow simulations an improvement of the compressor performance with larger fillet radius is observed. Modifying the fillet radius mainly influences the flow downstream of the blade trailing edge. Even though the impeller efficiency decreases as the fillet size gets larger, due to the increased tip leakage flow, the diffuser performance improves, leading to an overall increase of the compressor efficiency. The improvement of the diffuser performance is attributed to the lower static pressure at the trailing edge as the fillet radius increases. The lower static pressure allows the flow to get sucked out from the backwards facing step and to distribute over the whole span of the diffuser. On the one hand, this leads to increased mixing losses. On the other hand, the entrapment of the flow at the backwards facing step can be avoided in that way, which overall leads to a reduced total pressure loss in the diffuser
Datengetriebene Modellierung in der Messtechnik - Eine kurze Einführung, aktuelle Entwicklungen und Zukunftsperspektiven Data-driven modeling in metrology - A short introduction, current developments and future perspectives
No full text480503Mathematical models are vital to the field of metrology, playing a key role in the derivation of measurement results and the calculation of uncertainties from measurement data, informed by an understanding of the measurement process. These models generally represent the correlation between the quantity being measured and all other pertinent quantities. Such relationships are used to construct measurement systems that can interpret measurement data to generate conclusions and predictions about the measurement system itself. Classic models are typically analytical, built on fundamental physical principles. However, the rise of digital technology, expansive sensor networks, and high-performance computing hardware have led to a growing shift towards data-driven methodologies. This trend is especially prominent when dealing with large, intricate networked sensor systems in situations where there is limited expert understanding of the frequently changing real-world contexts. Here, we demonstrate the variety of opportunities that data-driven modeling presents, and how they have been already implemented in various real-world applications.91
Analysing micrologistics initiatives in rural areas – Approaches to typologise and assess complex logistics solutions in regional supply networks
No full textWhile demand for regional products increases and societal expectations towards a regionalisation of production are on the rise in Germany, little attention is given to the logistical challenges of local producers. At the same time, rural areas are confronted with declining supply options for goods of daily needs. Logistical challenges in rural areas are primarily caused by a scarcity of actors, low or fluctuating quantities of goods and long transport distances. A lack of economies of scale makes supply and logistics very costly. Given the rising interest and new possibilities created by digitisation, numerous private and public initiatives are developing solutions for sustainable regional logistics to secure and improve supply in rural areas - so called micrologistics solution. However, a meta-analysis of such regional logistics solutions is missing that identifies similarities and differences and indicates which characteristics are essential for the development of long-term viable regional logistics solutions. This article therefore aims at providing a general overview and at systematising current micrologistics solutions in rural regions, introducing a typology which is based on a meta-analysis of approximately 80 micrologistics initiatives in Germany and beyond. Referring to two case studies – Smart Village St. Wendel and UCKER Warentakt - we then focus analysis on solutions aiming at providing goods of daily need to the population in rural areas. We share lessons learnt on their characteristics, challenges and factors of success. This is done using a specifically developed morphological box, a viability and impact-oriented assessment framework for micrologistics initiatives as well as results of interviews with initiators and operators of such initiatives. We conclude on the usefulness of the analytical approaches developed for this new research field as well as further research needs.11
Cellular and Molecular Mechanisms of Mast Cells in Atherosclerotic Plaque Progression and Destabilization
No full text3049Mast cells (MCs) are commonly recognized for their crucial involvement in the pathogenesis of allergic diseases, but over time, it has come to light that they also play a role in the pathophysiology of non-allergic disorders including atherosclerosis. The involvement of MCs in the pathology of atherosclerosis is supported by their accumulation in atherosclerotic plaques upon their progression and the association of intraplaque MC numbers with acute cardiovascular events. MCs that accumulate within the atherosclerotic plaque release a cocktail of mediators through which they contribute to neovascularization, plaque progression, instability, erosion, rupture, and thrombosis. At a molecular level, MC-released proteases, especially cathepsin G, degrade low-density lipoproteins (LDL) and mediate LDL fusion and binding of LDL to proteoglycans (PGs). Through a complicated network of chemokines including CXCL1, MCs promote the recruitment of among others CXCR2+ neutrophils, therefore, aggravating the inflammation of the plaque environment. Additionally, MCs produce extracellular traps which worsen inflammation and contribute to atherothrombosis. Altogether, evidence suggests that MCs actively, via several underlying mechanisms, contribute to atherosclerotic plaque destabilization and acute cardiovascular syndromes, thus, making the study of interventions to modulate MC activation an interesting target for cardiovascular medicine.66
Remote Oscillator Characterisation Method for Netted Radar Systems
No full textA method to characterise a remote local oscillator from a radar transmitter of choice is described. It is achieved by sampling a transmitted signal with an USRP at selected time intervals. With the intention to save processing resources, after a first coarse estimation of the transmitted signal periodicity, recursively smaller sampling windows at selected time intervals are being used. The developed algorithm updates a selection window and chooses the most likely time of arrival within the sampled period, with a comparison to the previous measurements. The proposed method saves RF front-end utilisation time while allowing a real-time oscillator characterisation to be remotely carried-out. Sampling occurs at selected time intervals and allows to interleave the characterisation function with other radar modes of operation. At the expense of a lower oscillator characterisation accuracy when compared to characterising the remote oscillator with laboratory equipment using a larger sampling rate, the source remote oscillator may be characterised within a shorter period of time after a certain number of successful measurements. This method enables each receiver within a netted radar to periodically maintain a statistic regarding the behaviour of the local oscillator used by each transmitter of interest. It serves the purpose to provide side information regarding clock stability to aid the time synchronisation process between a receiver and a transmitter of choice
The genome of the Arctic snow alga Limnomonas spitsbergensis (Chlamydomonadales)
No full textSnow algae are a diverse group of extremophilic microeukaryotes found on melting polar and alpine snowfields. They play an important role in the microbial ecology of the cryosphere, and their propagation on snow and ice surfaces may in part accelerate climate-induced melting of these systems. High-quality snow algae genomes are needed for studies on their unique physiology, adaptive mechanisms, and genome evolution under multiple forms of stress, including cold temperatures and intense sunlight. Here, we assembled and annotated the genome of Limnomonas spitsbergensis, a cryophilic biciliate green alga originally isolated from melting snow on Svalbard, in the Arctic. The L. spitsbergensis genome assembly is based primarily on the use of PacBio long reads and secondly Illumina short reads, with an assembly size of 260.248 Mb in 124 contigs. A combination of 3 alternative annotation strategies was used including protein homology, RNA-seq evidence, and PacBio full-length transcript isoforms. The best merged set of annotations identified 18,277 protein-coding genes, which were 95.2% complete based on Benchmarking Universal Single-Copy Orthologs analysis. We also provide the annotated mitogenome, which is a relatively large 77.942 kb circular mapping sequence containing extensive repeats. The L. spitsbergensis genome will provide a new resource for research on snow algae adaptation, behavior, and natural selection in unique, low-temperature terrestrial environments that are under threat from climate change.14
Energy Management for Industrial Robots based on AutomationML
No full text25482553Motivated by political regulations and rising energy prices, companies strive for implementing energy management and for reducing their energy consumption. It is an expenditure of work for the energy manager to gather all relevant information about the facilities and machines (e.g. meaning of measurement and control signals, limits of these quantities, installed nominal capacities). In many cases, there is digital planning data from the planning, construction and commissioning phases. Using AutomationML, this information can be used collaboratively not only for engineering and maintenance but for energy monitoring and optimization. In this study, an industrial robot and two conveyors are integrated in the wide-spread energy management software suite EnEffCo. We document the method and results. Implications for deriving optimization formulations are discussed
