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J. Ubacht

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68 records found

Journal article (2026) - Abdulkhamid Mukhamedov, Vanessa Simões de Azevedo, Michel van Eeten, Jolien Ubacht, Yury Zhauniarovich
The growing economic value of blockchain-driven financial applications brings increasing risks. In recent years, EU regulators felt the urgent need to address the financial and security risks that digital currencies might pose if left unsupervised. In 2020, the European Commission proposed a draft regulation called Markets in Crypto-Assets (MiCA). It sets out the rules for the crypto-asset issuers and service providers located in the EU or serving EU clients. To date, there is no evaluation of the risks covered by the proposed regulations besides the Commission’s own evaluation.

We conducted a study to identify the risk perceptions of different stakeholder groups in the market by interviewing 20 representatives of Crypto-Asset Service Providers, Crypto-Asset Issuers, Institutional Investors, and Legal Experts. We then compared the risks deemed relevant by the stakeholder groups with the risks covered in the MiCA framework. That allowed us to identify which risks and stakeholder groups’ concerns are insufficiently covered by the current version of the MiCA framework. As a result, we show that Crypto-Asset Issuers’ risks are the least addressed in the current MiCA version. Specifically, residual risks remain with regard to smart contracts, oracles, and transactions. These risks should be considered for upcoming amendments to the regulation. ...
Journal article (2025) - Jolien Ubacht, Manuel Pedro Rodríguez Bolívar, Panos Panagiotopoulos, Peter Parycek, Gabriela Viale Pereira, Gerhard Schwabe, Anthony Simonofski, Efthimios Tambouris, Vera Spitzer, Maurus Engbers, Simone Nicosanti, Lieselot Danneels, Roel Dobbe, Sara Hofmann, Marijn Janssen, Ida Lindgren, Euripidis Loukis, Francesco Mureddu, Anna Sophie Novak
Journal article (2025) - Y.C.M. Dumas, J. Ubacht, E. van Andel, Lily Akorfa Keledorme
Smallholder farmers in the Ashanti region of Ghana face challenges due to shifts in climate patterns that have a significant negative impact on their crop yields. We conducted a feasibility study into the transition toward an agroforestry system by integrating trees and shrubs within crop fields. In this research, we adopted a complex systems perspective to analyse the institutional, social, and technical aspects that play a role in such a transition. By conducting in-depth analyses through three rounds of interviews and a Q-sort method with smallholder farmers in the Ashanti region, we mapped the most important challenges in transitioning to an agroforestry system. These pertain to: uncertainties in land tenure agreements, the absence of effective conflict resolution mechanisms, having no knowledge of and tools for maintaining trees, and the lack of financial resources for upfront investments. Based on our findings, we provide recommendations for the design of the transition process toward a comprehensive agroforestry system in Ghana. We recommend improving land tenure security and establishing conflict resolution mechanisms by polycentric coordination in which all stakeholders are involved for this essential institutional redesign process. To enable smallholder farmers to acquire the required skills and tools for tree crops, preferably a pilot plot for real-life demonstration is initiated. Financial resources for the smallholder farmers in the transition period need to be warranted, e.g., via the design of a carbon credit market. We recommend future research to explore the perspective and interests of chiefs/landowners in the Ashanti region who have crucial decision-making power through their land ownership. ...

Unveiling the potential of human-LLM collaboration in the ontology extension process

Journal article (2025) - Julia García-Fernández, Jack Verhoosel, Jolien Ubacht, Roos Marieke Bakker
In this paper, we present a domain-independent ontology extension workflow supported by LLMs. Ontology Engineering (OE) is a complex field that requires combining technical skills with domain expertise across multiple disciplines. Despite numerous attempts at automation, most of the processes are still manual. Different ontology engineering methodologies coexist, but none is a standard. These challenges, together with the lack of highly skilled workers in the sector, increase the entry barriers to the field. In parallel, Large Language Models (LLMs) are becoming prominent in ontology development due to their natural language processing and coding capabilities and their reportedly emergent abilities. In this paper, we focus on human-LLM collaboration for ontology extension. Following a Design Science Research approach, we interviewed 11 experts and modeled the current process of ontology extension to disclose its main issues. We analyzed the concerns and opportunities perceived by ontology engineers for using LLMs. Based on our insights and previous work, we designed a process framework for ontology extension that combines human expertise with LLMs capabilities, providing customizable prompt templates, OE tools, and guidelines. We tested our methodology with an existing greenhouse ontology using GPT-4o. Finally, we qualitatively evaluated the results against a manually crafted extension we use as our gold standard. The results show that the proposed approach holds the potential to (1) get inspiration for adding new entities, (2) deal with complex syntax definitions and repetitive tasks, and (3) verify whether the extended ontology conforms to the requirements and competency questions. ...

EGOV-CeDEM-ePart 2025 conference

Conference paper (2025) - Sara Hofmann, Lieselot Danneels, Roel Dobbe, Anna Sophie Novak, Peter Parycek, Gerhard Schwabe, Vera Spitzer, Jolien Ubacht

Opportunities for Cross-Border eCommerce Risk Management

Journal article (2025) - Boriana Rukanova, Toni Männistö, Jolien Ubacht, Yao Hua Tan, Frank Janssens, Susana Wong Chan
Cross-border eCommerce flows from non-EU countries with direct product delivery to consumers in the European Union have been rapidly growing. Whereas monitoring eCommerce flows for aspects such as Value- Added Tax (VAT), and safety and security already is a high priority, the increasing volumes bring new concerns. Such concerns include how to ensure that the products are sustainably produced and how to ensure a level playing field with products that are produced in the EU or imported via other modes of transport that are subject to more thorough checks at the border. These challenges have become new priorities in EU policy documents. Currently, authorities receive limited information related to eCommerce goods (particularly the low-value consignments that are exempted from duties), which hampers their risk assessment. Recently, Digital Product Passports (DPPs) have been introduced in legislation as a tool to inform consumers, recyclers, and market surveillance authorities about the material and manufacturing aspects of products. These DPPs promise to contain rich data that can be used to enhance both the monitoring and the customs risk assessment of cross-border eCommerce flows. To assess the exact potential and added value of DPPs, we analyze international eCommerce flows in the context of the EU-funded project PARSEC. We identify potential areas where DPPs can be relevant for eCommerce monitoring and risk assessment and present follow-up research directions on this topic. ...

Conceptualizing Data, Information and IT Tools for Effective Policymaking

Journal article (2025) - Michiel Pauwels, Jolien Ubacht, René Reich, Boriana Rukanova, Luc Alaerts
As interest in circular economy governance grows, effective policymaking requires the creation and continuous monitoring of circular policies. In response, governments worldwide are seeking data and developing indicators to monitor and report progress within their jurisdictions. In recent years, this has led to a proliferation of monitoring frameworks at national, regional, and city levels. Nevertheless, existing research has yet to sufficiently address what types of information are essential for effective CE policymaking, how policymakers and enforcement agencies can access relevant data sources, and how information systems can support policymaking processes. This participatory workshop presents ongoing research on a conceptual framework that identifies key data attributes, information types, and digital infrastructures needed for CE policymaking. It aims to bring together researchers and policymakers working in open data, sustainability, smart cities, and evidence-based governance to discuss challenges, share best practices and build capacity through dialogue with fellow researchers and policymakers. ...

Opportunities for Cross-Border eCommerce Risk Management

Preprint (2025) - B.D. Rukanova, Toni Männistö, J. Ubacht, Y. Tan, Frank Janssens, Susana Wong Chan
Cross-border eCommerce flows from non-EU countries with direct product delivery to consumers in the European Union have been rapidly growing. Whereas monitoring eCommerce flows for aspects such as Value- Added Tax (VAT), and safety and security already is a high priority, the increasing volumes bring new concerns. Such concerns include how to ensure that the products are sustainably produced and how to ensure a level playing field with products that are produced in the EU or imported via other modes of transport that are subject to more thorough checks at the border. These challenges have become new priorities in EU policy documents. Currently, authorities receive limited information related to eCommerce goods (particularly the low-value consignments that are exempted from duties), which hampers their risk assessment. Recently, Digital Product Passports (DPPs) have been introduced in legislation as a tool to inform consumers, recyclers, and market surveillance authorities about the material and manufacturing aspects of products. These DPPs promise to contain rich data that can be used to enhance both the monitoring and the customs risk assessment of cross-border eCommerce flows. To assess the exact potential and added value of DPPs, we analyze international eCommerce flows in the context of the EU-funded project PARSEC. We identify potential areas where DPPs can be relevant for eCommerce monitoring and risk assessment and present follow-up research directions on this topic.

Pre-print paper to be presented at the EGOV2025 – IFIP EGOV-CeDEM-EPART’25, August 31 – September 4, 2025, Krems, Austria and is to appear in the the CEUR-WS Proceedings of Ongoing Research, Practitioners, Posters, Workshops, and Projects of the International Conference EGOV-CeDEM-ePart 2025. ...

Conceptualization of Data Sources and Information

Journal article (2025) - Michiel Pauwels, Jolien Ubacht, René Reich, Boriana Rukanova, Jelmer Lennartz, Luc Alaerts, Elmer Rietveld, Yao Hua Tan, Karel Van Acker
The EU Green Deal and the ensuing policies and regulations to stimulate the transition toward a circular economy pose challenges to policymakers and authorities. Taking planetary boundaries into account is a nascent topic on all regulatory levels, and data-driven policymaking and its implementation require the collection and access to new types of data in all policy-making phases, from agenda-setting to policy formulation, implementation, and evaluation. Extant studies into data-driven policymaking have not yet addressed which information types are needed and how policymakers and enforcement agencies can gain access to data sources, whereas the urgency to prepare for this is high. We use the lens of the policy cycles to assess the required data. In three typical cases, we explore the data sources at different policy levels of monitoring to develop a conceptual framework of data attributes to inform policymakers. We position that the extant data used in the policy phases for the transition to the circular economy are different from the familiar data that public administrations use in their respective domains. Our conceptual framework provides an initial overview of new types of data and potential shared use among the policy phases to support policymakers and enforcement agencies to timely prepare for access to the relevant data and data sources. We recommend the creation of data ecosystems for public administrations, the adoption of new capabilities for CE literacy, exploring the added value of Digital Product Passports, and AI-based tools and mechanisms to handle large volumes of data to structure messy data. ...
Journal article (2024) - J. Schmid, J. Ubacht, S.H. van Engelenburg, Jan van Oudheusden, E.J.L. Chappin
Energy production and consumption are major contributors to greenhouse gas (GHG) emissions, exacerbating one of the greatest challenges faced by modern societies: climate change. Thus, societies must switch to more sustainable energy sources. Green hydrogen has emerged as a promising alternative energy carrier, facilitating storage and utilization across various industries. However, amidst different production processes, solely sustainable electrolysis stands out as an environmentally benign production method. Hydrogen producers must prove provenance and sustainable production to regulatory bodies and hydrogen buyers to comply with the regulations for sustainable development. Blockchain provides a viable solution encompassing trustworthy and secure information sharing between untrusted partners. In this article, we employ a design science research approach to develop a blockchain-based certification system (BLC-CS) for green hydrogen. Through collaboration with experts to gather requirements and conduct evaluations, we design an artifact that streamlines the certification process for producers, regulators, and consumers. Our proposed solution facilitates information gathering, verification, and reporting, contributing to the advancement of sustainable energy practices. We provide a comprehensive discussion of the BLC-CS’s feasibility for green hydrogen certification, including technical extensions, recommendations for practitioners, and directions for future research. ...
Journal article (2024) - Boriana Rukanova, Jelmer Lennartz, Wirawan Agahari, Jonathan Schmid, Jolien Ubacht, Yao Hua Tan, Elmer Rietveld, Theodor Chirvasuta
To facilitate the transition toward a circular economy (CE), EU policymakers are drafting new policies and legislations at a high speed. This affects a wide set of sectors and leads to legislative complexity. At the same time, the legislative developments requiring Digital Product Passports (DPPs) offer opportunities for governments to tap into a rich set of business supply chain data for CE and sustainability monitoring. Nevertheless, the diversity of these legislative initiatives leads to complexity for governments on what needs to be monitored. There is a need to reduce legislative complexity, to have a more clear view on what governments need to monitor, which in turn would provide more clarity on the types of business data from the Digital Product Passports and digital infrastructures governments may need to access for CE and sustainability monitoring purposes. One approach to reduce the legislative complexity is to have a framework of high-level concepts for CE and sustainability monitoring. The question, however, is how to arrive at such a framework of high-level concepts. In this paper, we explore the potential of the concepts found in the UN Recommendation 46 (initially developed for the traceability of textiles), to serve as a basis for a generic framework of high-level concepts for CE and sustainability monitoring. We examine the suitability by applying the concepts from UN Recommendation 46 to a variety of legislations beyond textiles. Our analysis suggests that the framework has the potential to serve as a high-level framework of CE and sustainability monitoring concepts across sectors, and we identify several areas for further research. ...
Conference paper (2024) - Boriana D. Rukanova, Jolien Ubacht, Yao Hua Tan
Circular economy (CE) and sustainability are high on the political agenda of governments nationally and internationally. We see different regulatory developments where governments aim to put stricter rules and requirements towards businesses to ensure the transition toward a more circular and sustainable future. The use of digital infrastructures, including transparency systems and digital product passports is starting to play a vital role in supporting governments in their CE monitoring efforts. Yet there are challenges to be overcome. Many government procedures are set up in laying out very detailed requirements about what one government agency can do in a singular phase of the circular process (e.g., customs performing specific checks at the border) or a single Member State (e.g., organizing Extended Producer Responsibility in a specific country). While these efforts are valuable building stones towards CE monitoring, they are fragmented, and blank spots in CE monitoring occur when borders are crossed, and another country needs to take over the CE monitoring tasks. As for circularity, even if many efforts are spent by a single government agency or a single country, all these efforts may be in vain if the proper CE monitoring of the next step is not secured. While earlier research identified this problem, there is still limited understanding of the problem itself and directions to address it systematically. In this paper, following up on earlier research and with insights gained from an EU project on CE monitoring, we shed further light on the problem. More specifically we conceptualize CE monitoring by putting the CE flows at the center and exploring deficiencies for governments and businesses to safeguard the monitoring of CE flows. We examine two routes that can be followed to ensure continued CE monitoring when borders are crossed, namely the government route, as well as the business route (enabled by traceability systems and in-control mechanisms of businesses). We discuss the need for a global governance layer that can facilitate both routes and propose further directions to advance CE monitoring by taking a global perspective. ...
Journal article (2024) - Marius Rohde Johannessen, Csaba Csáki, Lieselot Danneels, Sara Hofmann, Thomas Lampoltshammer, Peter Parycek, Gerhard Schwabe, Efthimios Tambouris, Jolien Ubacht
Journal article (2024) - Jolien Ubacht, Joep Crompvoets, Sara Hofmann, Peter Parycek, Gabriela Viale Pereira, Gerhard Schwabe, Iryna Susha, Efthimios Tambouris, Csaba Csáki, Lieselot Danneels, Marijn Janssen, Marius Rohde Johannessen, Thomas Lampoltshammer, Habin Lee, Ida Lindgren, Anastasija Nikiforova
Conference paper (2024) - Wout Hofman, B.D. Rukanova, Y. Tan, Nitesh Bharosa, J. Ubacht, Elmer Rietveld
The transition towards a circular economy (CE) will require data sharing across different platforms and data spaces of parties operating in a variety of supply chains. From a circular economy compliance monitoring perspective, beyond the access to mandatory data that governments will receive, authorities may benefit from accessing additional business data from the source on a voluntary basis, which is challenging. While platforms and data spaces solve a great deal of complexity and interoperability within their realm, platform, and data space interoperability is still challenging. In the logistics domain, efforts have been made to overcome these issues of data sharing across logistics platforms with a Semantic data sharing architecture developed by the CEF FEDeRATED Action, at the heart of which is a semantic model aligning other semantic models for logistics. In this paper, we take the Semantic data sharing architecture as a point of departure and examine the opportunities and limitations that it has for CE monitoring, and how it relates to other developments in the EU and beyond. Many of these developments acknowledge the need for data access across heterogeneous systems and – processes of actors; others add security and trust to data sharing that goes all the way to the level to cover legal obligations. The goal of this paper is to gain further insights into how data sharing across multiple platforms and data spaces enables circular economy monitoring, where government organizations would need to address the issue of how they would interface with, and access data that resides in multiple platforms and data spaces. We found that the various models can be aligned on some architecture principles that promote interoperability across dimensions (e.g. federation, keeping data at the source), yet they still differ on other dimensions (e.g. data model and semantics, as well as how they address issues of identification, authentication and authorization). We suggest further efforts towards developing meta-level agreements and standardization for data space interoperability and we propose further research directions on that topic. ...
Journal article (2024) - Vannesya Harahap, Linda M. Kamp, Jolien Ubacht
As a primary means of communication, the role of mobile telecommunications networks is important for a developing country's economic and social development. However, especially rural areas in low-income countries still lack mobile coverage. In the academic literature, only segmented solution strategies for this mobile coverage problem in rural areas are proposed. These are either technological, regulatory, or organizational solutions, whereas solving the mobile coverage gap requires an integrated approach to develop arrangements for mobile network rollout in rural areas. This paper presents a comprehensive overview of the causes of the lack of mobile coverage, the available solutions, and how they can be combined. Based on this overview, the paper proposes a decision support scheme for selecting a suitable arrangement for solving the mobile coverage gap. In this decision support scheme, the technical, organizational, and regulatory solutions are combined to develop a set of arrangements that match the local key causes of the lack of mobile coverage and that fit with the local context. In the last phase of the decision support scheme, the relevant stakeholders are involved in selecting the most suitable arrangement. We demonstrate the decision support scheme by applying it to the case of an unserved rural village in Indonesia, Unipa on the island of Papua, to show how it can guide a developing country to initiate the process of developing a solution for mobile coverage problems in rural areas. ...

An Exploratory Study in the Domain of Battery Circularity

Monitoring the circular economy (CE) transition requires data sharing and collaboration between public and private actors. However, businesses are reluctant to share data with authorities for monitoring purposes due to fear of losing control over sensitive data. The emerging technology Multi-Party Computation (MPC), which enables collaborative data analysis while maintaining data control, could address barriers in business-to-government (B2G) data sharing and collaboration. This ongoing research aims to explore the potential of MPC in facilitating B2G data sharing and collaboration for CE monitoring under the conditions of inter-organizational trust and data control. Drawing on a B2G data sharing framework, our initial findings suggest that MPC can benefit authorities in accessing sensitive business data, while businesses can benefit from controlling shared data for compliance reporting. As MPC can be deployed in various architectures, the next research steps are to examine links between variants of MPC architectures and different data-sharing solutions. ...
Preprint (2024) - W. Hofman, B.D. Rukanova, J. Ubacht, Y. Tan, E. Rietveld, J. Lennartz, W. Agahari, T. Chirvasuta, J. Schmid
To access business data for compliance monitoring of the circular economy (CE), governments would need to deal with issues of both legislative complexities arising from many new regulations in the area of CE and sustainability, as well as the digital complexity for accessing business data that resides in different business systems and data spaces. While earlier research has touched upon (1) the legal complexity through the identification of common high-level concepts of what to monitor, and (2) the digital complexities through the use of upper ontologies, so far these aspects have been treated to a large extent in isolation and not been linked systematically. In this research in progress paper, we propose an approach on how to link the two, discuss advances in the area and limitations, and identify areas that need to be addressed to allow governments to tap into the rich business data sources for compliance monitoring in the future. ...
The AI Act represents a significant legislative effort by the European Union to govern the use of AI systems according to different risk-related classes, imposing different degrees of compliance obligations to users and providers of AI systems. However, it is often critiqued due to the lack of general public comprehension and effectiveness regarding the classification of AI systems to the corresponding risk classes. To mitigate these shortcomings, we propose a Decision-Tree-based framework aimed at increasing legal compliance and classification clarity. By performing a quantitative evaluation, we show that our framework is especially beneficial to individuals without a legal background, allowing them to enhance the accuracy and speed of AI system classification according to the AI Act. The qualitative study results show that the framework is helpful to all participants, allowing them to justify intuitively made decisions and making the classification process clearer. ...
The AI Act represents a significant legislative effort by the European Union to govern the use of AI systems according to different risk-related classes, linking varying degrees of compliance obligations to the system's classification. However, it is often critiqued due to the lack of general public comprehension and effectiveness regarding the classification of AI systems to the corresponding risk classes. To mitigate those shortcomings, we propose a Decision-Tree-based framework aimed at increasing robustness, legal compliance and classification clarity with the Regulation. Quantitative evaluation shows that our framework is especially useful to individuals without a legal background, allowing them to improve considerably the accuracy and significantly reduce the time of case classification. ...