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Evidentiality and flexibility of source reporting
No full textThe reporting of the sources of our statements—whether we have, e.g., seen something or been told something—plays an important role in communication. The inaccurate reporting of sources is often associated with the spread of inaccurate beliefs, as when rumors are attributed to a non-existent credible source. Experiments have revealed that participants display a substantial amount of flexibility in the reporting of sources, in particular by attributing to themselves ideas they have acquired from others. However, these participants belonged to large-scale societies, and they spoke languages without grammatical evidential marking. Both factors might increase flexibility in source reporting. To test whether members of small-scale societies speaking languages with evidential marking also display flexibility in source reporting, we conducted two experiments with Quichua and Cha’palaa speakers in Ecuador. In both experiments, some participants acquired a belief through social transmission, and then had to communicate this belief to another participant. In doing so, very few participants mentioned the social source of their belief, whether explicitly, or by using the relevant evidential markers. These results show that flexibility in source reporting is a cross-culturally robust phenomenon, and that grammatical evidential marking does not appear to strongly affect this flexibility
Intercomparison of Earth Observation products for hyper-resolution hydrological modelling over Europe
No full textThe increasing frequency and severity of hydrological extremes demand the development of early warning systems and effective adaptation and mitigation strategies. Such systems and strategies require spatially detailed hydrological predictions, mostly provided by hydrological models. However, current state-of-the-art hydrological predictions remain limited in their spatial resolution. A proposed solution is the integration of high-resolution (0.5 with the benchmark reference over most areas and are recommended for hyper-resolution hydrological modelling over Europe. The MODIS (resolution of 250 m) and Sentinel-2/Landsat-8 (resolution of 20/30 m) snow cover products showed the highest classification accuracy and were selected as the best choice for the use of snow cover area products in hyper-resolution hydrological modelling. For surface soil moisture, the NSIDC SMAP product at 1 km resolution yielded correlation coefficients >0.6 at most stations and is recommended for hyper-resolution hydrological modelling. Finally, evapotranspiration products showed similar performances at the selected flux sites (correlations coefficients > 0.8). While the MODIS-Terra/Aqua evapotranspiration products (MOD16A2/MYD16A2) offer higher spatial resolution (500 m), making them potentially advantageous for hyper-resolution hydrological modelling, their temporal resolution is coarser (8-day intervals). In contrast, products like ETMonitor (1 km), ALEXI, and HOLAPS (5 km) provide daily estimates, albeit at lower spatial resolution. The assimilation of the proposed high-resolution products in models individually or in combination could lead us to hyper-resolution hydrological modelling. Still, developing integration workflows is required to overcome difficulties related to scale mismatches and data-gaps
Photocatalytic upcycling of PET into methane, hydrogen and high-value liquid products
No full textThe harmful effects of daily plastic use are increasingly evident, with most waste burned or landfilled, leading to the formation of microplastics that pollute the environment and the food chain. While the full impact remains unclear, photoreforming of plastics has emerged as a promising sustainable abatement method. This study demonstrates the commercial potential of P25 TiO₂ towards photocatalytic upcycling of polyethylene terephthalate (PET) microplastics by systematic exploration of the effect of co-catalysts, reaction temperature and oxygen presence on the generation of solar fuels and high-value liquid products. We demonstrate that while neat P25 yields minimal H₂ evolution, increasing the reaction temperature enhances its production significantly, and the addition of Pt further boosts H₂ generation by four orders of magnitude, resulting in 15.35 µmol h⁻¹ of H₂ and apparent quantum yield (AQY) values up to 0.45%. On par with H₂, we observe the generation of CH₄ from the reaction mixture, which we conclude to originate directly from PET rather than hydrogenation reactions. Liquid-phase analysis reveals diverse photoreforming products, including acetic acid, oxalic acid, formic acid and ethanol, with selectivity influenced by catalyst composition and reaction conditions. The feasibility of large-scale application of the process is further validated through prolonged irradiation tests using solar-simulated light and an upscaled setup, which demonstrate remarkable AQYs reaching 0.84%. These findings suggest PET photoreforming as a promising route for producing solar fuels and valuable chemicals, paving the way for sustainable plastic processing and upcycling
Verkehrsbeschränkungen als Beitrag zum Umwelt- und Klimaschutz
No full textAus Sicht des Umwelt- und Klimaschutzes stellen verkehrsbeschränkende Maßnahmen wie Geschwindigkeitsbeschränkungen oder Fahrverbote einen wichtigen Baustein der Mobilitätswende dar. Der Beitrag gibt einen Überblick, welche Instrumente für Verkehrsbeschränkungen im Interesse des Umweltschutzes im Straßenverkehrs- und Luftreinhalterecht bestehen. Unter Einbeziehung der wesentl europarechtl und verfassungsrechtl Rahmenbedingungen wird zudem aufgezeigt, vor welchen rechtl Herausforderungen die Umsetzung von Verkehrsbeschränkungen im Interesse des Klimaschutzes steht
Construction and operation of a lab reactor for catalytic carbon dioxide fixation producing chemicals
No full textEntsprechend den Vorgaben der EU-Kommission und der Bundesregierung soll Österreich bis 2050 bzw. 2040 „CO2-neutral“ werden. Um diesem ambitionierten Ziel näher zu kommen und den anthropogenen Treibhauseffekt zu begrenzen, bestehen für Umwelttechniker im Wesentlichen drei Handlungsfelder: die Öffentlichkeit zu einer ökologischeren bzw. CO2-ärmeren Lebensweise zu motivieren, industrielle Prozesse und Verfahren so zu optimieren, dass weniger CO2 emittiert wird oder bereits freigesetztes CO2 technisch zu fixieren. Diese Arbeit befasst sich mit der katalytischen Fixierung von CO2 in EtOH (Ethanol). Das dabei entstehende Diethylcarbonat (DEC) ist wirtschaftlich wertvoller als Ethanol und erfreut sich aufgrund seines vielseitigen industriellen Einsatzpotenzials zunehmender Nachfrage. Im Rahmen eines von der WAW geförderten Projekts wurde gemeinsam mit dem Projektpartner „kleinkraft OG“ ein Versuchsstand zur DEC-Synthese aufgebaut und die Versuchsdurchführung schrittweise optimiert. Zentrales Element war ein Hochdruckreaktor, der mit zwei eigens entwickelten Katalysatorkörben für Molekularsiebschüttungen betrieben wurde. In umfangreichen Versuchsreihen wurden die Prozessparameter Druck, Reaktionszeit und Eduktmengenverhältnis sowie verschiedene Katalysatoren variiert. Die erzielten Produktausbeuten und Produktqualitäten wurden analysiert, anschließend ausgewertet und mit Literaturwerten verglichen.According to the targets set by the European Commission and the Austrian government, Austria aims to become “CO2-neutral” by 2050 and 2040, respectively. To move closer to this ambitious goal and to limit the anthropogenic greenhouse effect, environmental engineers essentially have three fields of action: motivating the public to adopt a more ecological or CO2-reduced lifestyle, optimizing industrial processes and procedures to emit less CO2, or technically binding CO2 that has already been emitted. This work focuses on the catalytic fixation of CO2 in ethanol. The resulting product, diethyl carbonate (DEC), is economically more valuable than EtOH (ethanol) and enjoys increasing demand due to its versatile industrial applications. As part of a project funded by WAW, a test rig for DEC synthesis was built and the experimental procedure gradually optimized in collaboration with the project partner “kleinkraft OG.” The central component was a high-pressure reactor operated with two specially developed catalyst baskets filled with molecular sieve pellets. In extensive test series, the process parameters pressure, reaction time, and reactant ratio, as well as various catalysts, were varied. The resulting product yields and product qualities were analyzed, subsequently evaluated, and compared with literature data
Design of a nozzle test rig
No full textDiese Diplomarbeit setzt sich mit dem Entwurf eines Düsenprüfstandes auseinander. Dazu wird zuerst ein Blick auf bestehende Prüfstände geworfen und deren Aufbau analysiert, um daraus ein Design abzuleiten, welches die gestellten Anforderungen erfüllt. Hauptmotivation dieses Entwurfs ist es eine Prüfstandsumgebung zu schaffen, um einen Prüfling aus dem Forschungsprojekt exFan testen zu können. Dieses Projekt setzt sich mit der Frage auseinander, ob die Abwärme einer Brennstoffzelle eines wasserstoffbetriebenen Flugzeugs dazu genutzt werden kann, zusätzlichen Schub zu erzeugen. Die Abwärme soll mittels Wärmetauscher in den Luftstrom eines Mantelpropellers eingebracht werden und mithilfe des Meredith-Effekts beziehungsweise Junkers Düsenkühlerprinzips zur Schuberzeugung genutzt werden. Um das auf einem Prüfstand zu bewerkstelligen ist ein Luftstrom, welcher durch eine Verdichteranlage bereitgestellt wird, notwendig. Ebenso muss Wärmeenergie bereitgestellt werden, um den Wärmetauscher des Prüflings zu speisen. Des Weiteren muss die übertragene Wärme im Wärmetauscher und der erzeugte Schub des Prüflings genau gemessen werden, um auf den erreichten Effekt schließen zu können. Ein wichtiger Teil dieser Arbeit ist auch die Abschätzung der Prüfstandscharakteristik und die Erstellung von Kennfeldern, welche einen möglichen Betriebsbereich prognostizieren. Ebenso wird eine konkrete Konstruktion ausgeführt und mittels technischer Dokumentation und Zeichnungen festgehalten.This diploma thesis deals with the design of a nozzle test bench. To this purpose, existing test benches are first examined and their structure analysed in order to derive a design that meets the specified requirements. The main motivation for this design is to create a test bench environment in order to test a specimen from the exFan research project. This project deals with the question of whether the waste heat from a fuel cell in a hydrogen-powered aircraft can be used to generate additional thrust. The waste heat is to be introduced into the air flow of the ducted fan by means of a heat exchanger and used to generate thrust with the help of the Meredith effect or Junkers jet cooler principle. Therefore, it is necessary to provide an airflow by a compressor system, also to supply thermal energy to feed the test specimen's heat exchanger. Also, it is crucial to accurately measure the heat transferred in the heat exchanger and the thrust generated by the test object in order to precisely determine the effect achieved. An important part of this work is also the estimation of the test bench characteristics and the creation of characteristic maps that predict a possible operating range. A concrete design is also carried out and recorded by means of technical documentation and drawings
(Re)drawing the future. How we successfully analyse and design maps and plans for participation. Examples from the superblock processes in Barcelona and Vienna.
No full textKarten und Pläne sind eine Form von Macht. Sie können die Entwicklung hinzu einer faireren Gesellschaft vorantreiben oder sie bremsen. Ihr Potenzial wird besonders im Kontext von Bürger:innenbeteiligung sichtbar. Dort kommen siehäufig zum Einsatz, um den Weg für lebenswertere Städte zu ebnen. Vor diesem Hintergrund untersucht die Arbeit am Beispiel von zwei Superblock Fallstudien in Wien und Barcelona, wie Karten und Pläne in der Bürgerinnenbeteiligung zum Einsatz kommen. Dabei werden Ansätze für eine niederschwellige Kommunikation mit Karten und Plänen untersucht. Auf Basis dieser Recherche und desiterativen Ausprobierens entwickelt die vorliegende Arbeit ein Codebuch, um Karten und Pläne in der Bürger:innenbeteiligung strukturiert zu analysieren und zu konzipieren. Im Spannungsfeld zwischen Planung und Kartografie erforscht die vorliegende Arbeit, wie es gelingen, kann mit Karten und Plänen eine fairere Zukunft zu zeichnen.Maps and plans are a form of power. They can either promote or hinder the development of a fairer society. Their potential is particularly evident in the context of citizen participation, where they are often used to pave the way for more livable cities. Against this backdrop, the thesis examines how maps and plans are used in citizen participation, using two superblock case studies inVienna and Barcelona as examples. Approaches for low-threshold communication with maps and plans are examined. Based on this research and iterative testing,this work develops a code book for the structured analysis and design of maps and plans in citizen participation. In the field of tension between planning and cartography, this work explores how maps and plans can be used to draw a fairer future
A System Prototype for Food Sales Forecasting and Optimization to Reduce Food Waste for Short-Shelf-Life Products
No full textThe reduction of food waste is one of the major challenges of today for retailers and wholesalers. Large amounts of food are thrown
away on the retail and wholesale level per year. Since globally available resources are limited, preventing food waste is a very important
way to reduce the carbon footprint and even help protect the environment because the production of goods consumes both large amounts of energy and land. Preventing food waste is intertwined with the related problem of order generation. The generation of orders depends on accurate forecasts provided to the users. In this paper, we present a system description of a prototype that signicantly improves forecasts to facilitate the reduction of food waste through the use of machine learning to provide a basis for subsequent order optimization. Our system has been developed in cooperation with Austrian retailers and wholesalers who provide both real-world data and valuable insights into the inner workings of Austrian grocers. We present an overview of the system and the technologies utilized to achieve our goals. In addition, we also discuss the constraints and ethical considerations encountered. Our evaluation shows that our system can help achieve the goals of reducing food waste while being very useful to our project partners and, therefore, workable
in the real world
3D Style Transfer: Lifting 2D Methods to 3D and Enabling Interactive Guidance
Get PDF3D style transfer refers to altering the visual appearance of 3D objects and scenes to match a given (artistic) style, usually provided as an image. 3D style transfer presents significant potential in streamlining the creation of 3D assets such as game environment props, VFX elements, or largescale virtual scenes. However, it faces challenges such as ensuring multi-view consistency, respecting computational and memory constraints, and enabling artist control. In this dissertation, we propose three methods that aim at stylizing 3D assets while addressing these challenges. We focus on optimization-based methods due to the higher quality of results compared to single-pass methods. 0ur contributions advance the state-of-the-art by introducing: (i) novel surface-aware CNN operators for direct mesh texturing, (ii) the first Gaussian Splatting (GS) method capable of transferring both high-frequency details and large scale patterns, and (iii) an interactive method that allows directional and region-based control over the stylization process. Each of these methods outperforms existing baselines in visual fidelity and robustness. Across three complementary projects, we explore different facets of 3D style transfer. In the first project, we propose a method that creates textures directly on the surface of a mesh. By replacing the standard 2D convolution and pooling layers in a pre-trained 2D CNN with surface-based operations, we achieve seamless, multi-view-consistent texture synthesis without relying on proxy 2D images. In the second project, we transfer both high-frequency and large-scale patterns using GS, while addressing representation-specific artifacts such as oversized or elongated Gaussians. Furthermore, we design a style loss capable of transferring style patterns at multiple scales, resulting in visually appealing stylized scenes that preserve both intricate details and large-scale motifs. In the third project, we propose an interactive method that allows users to guide stylization by drawing lines to control pattern direction, and painting regions on both the 3D surface and style image to specify where and how specific style patterns should be applied. Through our extensive qualitative and quantitative evaluations, we show that our methods surpass state-of-the-art techniques. We also demonstrate their robustness across diverse 3D objects, scenes, and styles, highlighting the flexibility of the presented methods. Future work may explore extensions such as geometry modification for style-driven shape changes, more efficient !arge-scale pattern synthesis, temporal coherence in dynamic or video-based scenes, and refined interactive controls informed by direct artist feedback to better integrate creative intent into the stylization pipeline
C2M-DoT: Cross-modal consistent multi-view medical report generation with domain transfer network
No full textObjectives: In clinical practice, multiple medical images from different views provide valuable complementary information for diagnosis. However, existing medical report generation methods struggle to fully integrate multi-view data, and their reliance on multi-view input during inference limits practical applicability. Moreover, conventional word-level optimization often neglects the semantic alignment between images and reports, leading to inconsistencies and reduced diagnostic reliability. This paper aims to address these limitations and improve the performance and efficiency of medical report generation. Methods: We propose C2M-DoT, a cross-modal consistent multi-view medical report generation method with domain transfer network. C2M-DoT (i) uses semantic-based contrastive learning to fuse multi-view information to enhance lesion representation, (ii) uses domain transfer network to bridge the gap in inference performance across views, (iii) uses cross-modal consistency loss to promote personalized alignment of multi-modalities and achieve end-to-end joint optimization. Novelty and Findings: C2M-DoT pioneered the use of multi-view contrastive learning for the high semantic level of report decoding, and used a domain transfer network to overcome the data dependency of multi-view models, while enhancing the semantic matching of images and reports through cross-modal consistency optimization. Extensive experiments show that C2M-DoT outperforms state-of-the-art baselines and achieves a BLEU-4 of 0.159 and a ROUGE-L of 0.380 on the IU X-ray dataset, and a BLEU-4 of 0.193 and a ROUGE-L of 0.385 on the MIMIC-CXR dataset