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Closing data gaps with emission factors: a general method applied to EPDs in Brightway
No full text27642779Purpose: Missing data are a fundamental challenge in Life Cycle Assessment (LCA). A promising way to address such gaps is the direct use of already calculated environmental impact assessments of upstream products. Although companies increasingly publish environmental information like Environmental Product Declarations (EPD), there is still limited research on integrating those emission factors directly as LCA results within standard LCA software to ensure seamless accessibility.
Methods: This paper proposes a novel method that integrates aggregated emission factors from environmental product declarations (EPD) into LCI. The method includes reverse calculation and proxy selection. Thus, proxies represent ecosphere flows which allow inventory result calculation and characterization during life cycle impact assessment (LCIA). The method generates LCI databases from emission factors with corresponding proxies, which provide these emission factors as LCA results within common LCA programs.
Results and discussion: The approach is demonstrated by integrating the ökobaudat (OBD) database - containing EPDs - into the LCA software Brightway. An example of LCA calculations with data from conventional and EPD databases using Brightway is provided. This example illustrates how data gaps can be effectively filled in a user-friendly way by simultaneously using data with and without supply chain information.
Conclusions: The feasibility of incorporating data without supply chain information in conventional LCA software is demonstrated. The developed method increases user-friendliness, as only one LCA modelling and calculation is required when using data with and without process-based information simultaneously. Additionally, the presented method is not restricted to a specific set of data sources, emission factors, or LCA programs and is generally applicable.301
The Impact of Blockchain on Transparency and Trust in Sustainable Agri-Food Supply Chains
No full text369381In the past, the focus on blockchain-technology was on increasing transparency for increased sustainability in the agri-food industry. However, scholars and practitioners have only recently thought about the influence and role of blockchain use on increasing the industry's trust through transparency. Blockchain-technology has been proposed as an innovation to address actor’s trust issues and marketing challenges in sustainable product chains. This paper adds to this growing body of work by examining the role of blockchain in building trust with an explicit focus on the sustainable agri-food industry
Sensing-Aided Beamforming: The Impact of Distributed Sensing Network Geometry
No full text254260As modern wireless systems increasingly focus on high-frequency bands, accurate beamforming has become an essential component for ensuring high-rate data transmission and robust connections. To reduce the overhead and latency caused by beam training, radar sensing can be used to support beamforming by narrowing the search space. Following the concept of Integrated Sensing and Communication (ISAC), we employ a distributed sensing network with multiple bi-static links to localize the target. The estimated target position is then used to assist beamforming. In this paper, we specifically investigates the underlying sensing performance for the given network geometry. Our results show that the spatially inhomogeneous distribution of the Cramér-Rao Lower Bound (CRLB) can influence the Angle of Departure (AoD) estimation of beamforming, which highlights the importance of beamformer placement in the sensing network. Furthermore, we present a beamforming accuracy map, which can serve as a reference for optimizing placement strategies
Comprehensive Tutorial: Engineering AI Systems
No full text176177This Comprehensive Tutorial at ICSA 2025 is based on our upcoming book Engineering AI Systems: Architecture and Devops Essentials [1]. The main argument of this book is that the behavior and quality of software systems that use Artificial Intelligence (AI) stems from the AI part, the traditional software part, and the interactions between both. Achieving high-quality AI systems requires managing all of these aspects well, throughout the whole life cycle from architecture design through to operation & analysis. The tutorial extends over two 90-minute slots, and is split up in two halves accordingly. During the first half, we will cover basics of AI and Machine Learning (ML). In the second half, we will go into details of the core of the book, namely the life cycle of AI-based systems and various qualities of such systems
Component Dimensioning in Hydrogen Environment
No full text625632For the ongoing energy transition, high pressure hydrogen is a highly relevant energy carrier. In order to provide a practical and robust hydrogen infrastructure, a vast variety of components needs to be developed to ensure a save hydrogen storage and transport. Dimensioning of these parts with respect to their structural durability requires new dimensioning schemes and guidelines to be developed which account for material specific damage mechanisms under hydrogen environment. An ideal basis represents the well-established FKM guideline issued by the German Research Association Mechanical Engineering (FKM). The guideline is applicable for a wide range of mechanical engineering components and is particularly popular for small and medium enterprises. Within this work, the dimensioning scheme based on FKM guideline is applied for exemplary structural parts in hydrogen environment. Based on literature data and experiments conducted within the project, the fatigue strength assessment scheme acc. to the FKM guideline is modified and finally used for the assessment of a sample component from austenitic stainless steel. In our work, we analyze the applicability of the guidelines based on this dimensioning use case and discuss how the FKM approach needs to be adapted to consider the hydrogen effects on a general basis.7
Biomedical Knowledge Graphs: Context, Queries and Complexity
No full text529567Ontology-based mappings in knowledge graphs are a widely discussed topic in biomedical research. Contextual information is widely considered for NLP and knowledge discovery in life sciences since it highly influences the exact meaning of natural language. The scientific challenge is not only to extract such context data, but also to store this data for further query and discovery approaches. Classical approaches use RDF triple stores, which have serious limitations. Here, we introduce the graph-theoretic foundation for a general context concept within semantic networks and show a proof-of-concept based on biomedical literature and text mining as a multiple step knowledge graph approach using labeled property graphs based on polyglot persistence systems to utilize context data for context mining, graph queries, knowledge discovery and extraction. Our test system contains a knowledge graph derived from the entirety of PubMed and SCAIView data and is enriched with text mining data and domain specific language data using BEL. Here, context is a more general concept than annotations. Storing and querying a giant knowledge graph as a labeled property graph is still a technological challenge. Here we demonstrate how our data model is able to support the understanding and interpretation of biomedical data. We present several real world use cases that utilize our massive, generated knowledge graph derived from PubMed data and enriched with additional contextual data. Finally, we show a working example in context of biologically relevant information using SCAIView.11
Combining Knowledge Graphs and Language Models to Answer Questions over Tables
No full textTables remain a primary modality for organizing and presenting information to people. We interact every day with Excel sheets, CSV files, tables in PDF documents, and web tables. Providing a natural language interface to query table information is paramount for several use cases. This demo shows a solution to query semantically described tables using natural-language questions. Our solution employs knowledge graphs as a medium to integrate tables coming from heterogeneous sources. Then, a transformer-based language model analyzes a user's question and finds the answer in the semantically represented tables. During the demo session, we will show a use case developed in collaboration with DATEV eG, where tax consultants can efficiently query information from financial tables. Attendees will experience how a natural-language interface speeds up the information retrieval process from tables. They will also be allowed to ask their questions to a prepared dataset, showing the scalability of our solution. The video demo is available at https://owncloud.fraunhofer.de/index.php/s/uXFmUfzCta70rqN
Empirical model for room temperature thermal conductivity of WC-Co hardmetals
No full textHardmetals or cemented carbides are a widely used material for cutting tools due to their excellent mechanical properties. However, the tool’s ability to transfer heat, which is defined by the thermal conductivity, is also of high importance in view of the high temperatures which occur during metal cutting. In this work the measured thermal conductivity of various WC-Co hardmetals is correlated with the metallic binder content, which ranged between 5 wt% and 20 wt%, and the WC grain size, which was measured using linear intercept analysis and ranged between 0.1 µm and 2.4 µm. An empirical model to estimate the room temperature thermal conductivity of WC-Co hardmetals as a function of WC grain size and Co content is proposed and discussed
Analog Frontend for a Passive 5.8-GHz RFID Transponder in 130-nm CMOS Technology
No full text676679We present a 5.8-GHz RFID transponder frontend. It consists of a 3-stage charge pump/rectifier circuit, a demodulator circuit featuring the same charge pump topology, a single transistor modulator, allowing backscatter modulation, an LC-matching network, which matches the impedance of the transponder to a 175-Omega antenna, as well as ESD and overvoltage protection circuitry. The transponder frontend was characterized by wafer prober measurements yielding a sensitivity of -11 dBm and reflection coefficients of -18 dB when the modulator is in off-state and -5 dB when the modulator is in on-state. The RFID-frontend was also integrated into a demonstrator PCB, featuring a 175-Omega patch antenna. With the demonstrator PCB, demodulation of incoming signals, as well as backscatter modulation, could be demonstrated. The intended application is the electronic identification of sterile goods in medical facilities to comply with the new European medical device directive 2017/745
Analysis of the Feasibility Region of Hierarchical Flexibility Coordination Schemes
No full text195200This paper presents an analysis of the properties of timecoupled flexibility potentials and a method for analysing modelling and aggregation errors in hierarchical flexibility coordination schemes through synthetically generated flexibility demand timeseries. Central to the method is the generation of a uniform sampling of the flexibility potential’s feasible operating region. To that end, an interpretation of the convex solution space is conceived as an n-dimensional polytope and sampled using two different methods. It is shown that a sampling method based on markov-chains is better suited to generate feasible samples in complex flexibility potentials with timecoupling constraints than a rejection sampling method that requires a rectangular bounding-box around the n-dimensional description of the flexibility potential. We also show that assessments of flexibility coordination schemes should be done across the entire feasibility region and not be limited to the convex hull as coordination metrics, such as the aggregation error, are non-uniform across the feasibility region