References of "Fridgen, Gilbert 50038516"
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See detailPrivacy-preserving federated learning for residential short-term load forecasting
Delgado Fernandez, Joaquin UL; Potenciano Menci, Sergio UL; Lee, Chul Min UL et al

in Applied Energy (2022), 326

With high levels of intermittent power generation and dynamic demand patterns, accurate forecasts for residential loads have become essential. Smart meters can play an important role when making these ... [more ▼]

With high levels of intermittent power generation and dynamic demand patterns, accurate forecasts for residential loads have become essential. Smart meters can play an important role when making these forecasts as they provide detailed load data. However, using smart meter data for load forecasting is challenging due to data privacy requirements. This paper investigates how these requirements can be addressed through a combination of federated learning and privacy preserving techniques such as differential privacy and secure aggregation. For our analysis, we employ a large set of residential load data and simulate how different federated learning models and privacy preserving techniques affect performance and privacy. Our simulations reveal that combining federated learning and privacy preserving techniques can secure both high forecasting accuracy and near-complete privacy. Specifically, we find that such combinations enable a high level of information sharing while ensuring privacy of both the processed load data and forecasting models. Moreover, we identify and discuss challenges of applying federated learning, differential privacy and secure aggregation for residential short-term load forecasting. [less ▲]

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See detailAn in-depth investigation of the performance characteristics of Hyperledger Fabric
Guggenberger, Tobias; Sedlmeir, Johannes UL; Fridgen, Gilbert UL et al

in Computers and Industrial Engineering (2022), 173

Private permissioned blockchains are deployed in ever greater numbers to facilitate cross-organizational processes in various industries, particularly in supply chain management. One popular example of ... [more ▼]

Private permissioned blockchains are deployed in ever greater numbers to facilitate cross-organizational processes in various industries, particularly in supply chain management. One popular example of this trend is Hyperledger Fabric. Compared to public permissionless blockchains, it promises improved performance and provides certain features that address key requirements of enterprises. However, also permissioned blockchains are still not as scalable as centralized systems, and due to the scarcity of theoretical results and empirical data, their real-world performance cannot be predicted with the necessary precision. We intend to address this issue by conducting an in-depth performance analysis of Hyperledger Fabric. The paper presents a detailed compilation of various performance characteristics using an enhanced version of the Distributed Ledger Performance Scan (DLPS). Researchers and practitioners alike can use the various performance properties identified and discussed as guidelines to better configure and implement their Hyperledger Fabric network. Likewise, they are encouraged to use the DLPS framework to conduct their measurements. [less ▲]

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See detailThe EU's Digital Identity Policy: Tracing Policy Punctuations
Weigl, Linda UL; Amard, Alexandre UL; Fridgen, Gilbert UL et al

in Proceedings of the 15th International Conference on Theory and Practice of Electronic Governance (ICEGOV) (2022, October)

This paper analyzes the development of the European Union’s digital identity policy. The analysis focuses on the dynamics leading to a sudden shift from identity management as a sensitive topic under ... [more ▼]

This paper analyzes the development of the European Union’s digital identity policy. The analysis focuses on the dynamics leading to a sudden shift from identity management as a sensitive topic under national competence towards a common, harmonized, user-centric European Digital Identity Framework layering on top of Member States’ existing systems. We adopted a syncretic approach to Punctuated Equilibrium Theory and focused specifically on the concept of policy punctuations and policy image. Process tracing is used as a method to trace and interpret causal mechanisms of policy processes. The empirical analysis is grounded in elite interviews and policy documentation. To open up the black box of policy-making, we analyze and disaggregate the policy process. We thereby provide a better understanding of the historical-political and technological mechanisms that determine particular policy outcomes. [less ▲]

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See detailOptimal industrial flexibility scheduling based on generic data format
Bahmani, Ramin UL; van Stiphoudt, Christine UL; Potenciano Menci, Sergio UL et al

in Energy Informatics (2022, September 07), 5

The energy transition into a modern power system requires energy flexibility. Demand Response (DR) is one promising option for providing this flexibility. With the highest share of final energy ... [more ▼]

The energy transition into a modern power system requires energy flexibility. Demand Response (DR) is one promising option for providing this flexibility. With the highest share of final energy consumption, the industry has the potential to offer DR and contribute to the energy transition by adjusting its energy demand. This paper proposes a mathematical optimization model that uses a generic data model for flexibility description. The optimization model supports industrial companies to select when (i.e., at which time), where (i.e., in which market), and how (i.e., the schedule) they should market their flexibility potential to optimize profit. We evaluate the optimization model under several synthetic use cases developed upon the learnings over several workshops and bilateral discussions with industrial partners from the paper and aluminum industry. The results of the optimization model evaluation suggest the model can fulfill its purpose under different use cases even with complex use cases such as various loads and storages. However, the optimization model computation time grows as the complexity of use cases grows. [less ▲]

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See detailIndicators for assessing the necessity of power system flexibility: a systematic review and literature meta-analysis
Bhuiyan, Rajon UL; Weissflog, Jan; Schoepf, Michael UL et al

in Proceedings of the 18th International Conference on the European Energy Market (EEM) (2022, September)

There are different flexibility options to align power systems to volatile feed-in of renewable electricity sources. The flexibility options differ in the dimensions of time, spatiality, and resource type ... [more ▼]

There are different flexibility options to align power systems to volatile feed-in of renewable electricity sources. The flexibility options differ in the dimensions of time, spatiality, and resource type. To make policy decisions on future energy systems, it is necessary to get a top-down indication of how much power system flexibility is needed. With the ongoing energy transition, there is yet no comprehensive overview of indicators that describe which dimension of flexibility will be necessary to what extent for different energy systems. Therefore, this paper provides a first overview of indicators that can be used to assess the necessity of power system flexibility. Thus, we do a systematic literature review to identify indicators that allow us to estimate the necessity of power system flexibility. We conduct a meta-analysis of these indicators and categorize them as indicators that either stand for an increasing or decreasing necessity of power system flexibility. Our paper can help inform policy, assess needed changes to system operations, increase stakeholder acceptance and investor confidence in implementing new technology and measures. [less ▲]

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See detailTarzan and chain: exploring the ICO jungle and evaluating design archetypes
Bachmann, Nina M.; Drasch, Benedict; Fridgen, Gilbert UL et al

in Electronic Markets (2022), 32

The phenomenon of a blockchain use case called initial coin offering (ICO) is drawing increasing attention as a novel funding mechanism. ICO is a crowdfunding type that utilizes blockchain tokens to allow ... [more ▼]

The phenomenon of a blockchain use case called initial coin offering (ICO) is drawing increasing attention as a novel funding mechanism. ICO is a crowdfunding type that utilizes blockchain tokens to allow for truly peer-to-peer investments. Although more than \$7bn has been raised globally via ICOs as at 2018, the concept and its implications are not yet entirely understood. The research lags behind in providing in-depth analyses of ICO designs and their long-term success. We address this research gap by developing an ICO taxonomy, applying a cluster analysis to identify prevailing ICO archetypes, and providing an outlook on the token value market performance for individual archetypes. We identify five ICO design archetypes and display their secondary market development from both a short-term and a long-term perspective. We contribute to an in-depth understanding of ICOs and their implications. Further, we offer practitioners tangible design and success indications for future ICOs. [less ▲]

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See detailWe need a broader debate on the sustainability of blockchain
Rieger, Alexander UL; Roth, Tamara UL; Sedlmeir, Johannes UL et al

in Joule (2022), 6(6), 1137-1141

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See detailGuiding Refugees Through European Bureaucracy: Designing a Trustworthy Mobile App for Document Management
Amard, Alexandre UL; Höß, Alexandra UL; Roth, Tamara UL et al

in Drechsler, A.; Gerber, A.; Hevner, A. (Eds.) The Transdisciplinary Reach of Design Science Research. DESRIST 2022 (2022, May 25)

After being granted asylum in European countries, refugees need to go through a multitude of administrative processes before they can participate in society. However, these processes are often challenging ... [more ▼]

After being granted asylum in European countries, refugees need to go through a multitude of administrative processes before they can participate in society. However, these processes are often challenging, as refugees struggle to understand them, lack instructions for managing paperwork, and do not possess the required language skills. Prior research emphasizes the role of information and communication technologies to simplify and enable refugee-friendly administrative processes. However, recent research and existing applications mainly focus on information retrieval and do not offer assistance for understanding official letters, completing administrative forms, and managing corresponding documents. Furthermore, refugees are often reluctant to use existing applications as they do not trust their host country’s governments and public authorities. In this research, we aim to address this functional and trust gap. We follow a design science research approach to develop a design for a refugee-centric and trustworthy mobile application that assists refugees along administrative processes. In doing so, we identify three design principles that may guide the development of such applications for refugees. [less ▲]

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See detailDecentralised Finance's Unregulated Governance: Minority Rule in the Digital Wild West
Barbereau, Tom Josua UL; Smethurst, Reilly UL; Papageorgiou, Orestis UL et al

E-print/Working paper (2022)

Decentralised finance (DeFi) is a category of unlicensed, unregulated, and non-custodial financial services that utilise public, distributed ledgers like Ethereum. The Bloomberg Galaxy DeFi Index ... [more ▼]

Decentralised finance (DeFi) is a category of unlicensed, unregulated, and non-custodial financial services that utilise public, distributed ledgers like Ethereum. The Bloomberg Galaxy DeFi Index, launched in August 2021, includes nine Ethereum-based projects – non-custodial exchanges as well as lending and derivatives platforms. Each project is governed, at least in part, by a community of unregistered individuals that hold tradable voting rights tokens (also known as governance tokens). Voting rights tokens allow holders to vote on proposed changes to a DeFi project’s features, parameters, or rules. DeFi’s governance power is thus linked to the distribution and exercise of tokenised voting rights. Since DeFi projects are typically not managed by companies or public institutions, not much is known about DeFi’s governance. Regulators and law-makers from the United States recently asked if DeFi’s governance entails a new class of “shadowy” elites. In response, we conducted an exploratory, multiple-case study that focuses on the voting rights tokens issued by the nine projects from Bloomberg’s Galaxy DeFi index. Our mixed methods approach draws on Ethereum-based data about the distribution, trading, and staking of voting rights tokens, as well as project documentation and archival records. Our findings contribute knowledge about the entitlements of DeFi’s voting rights tokens, the initial distribution strategies, and the actual voting and delegation activity. Our principal finding is that DeFi’s voting rights are highly concentrated, and the exercise of these rights is very low. Our theoretical contribution is descriptive: minority rule is the probable consequence of tradable voting rights plus the lack of applicable anti-concentration or anti-monopoly laws. We interpret DeFi’s minority rule as timocratic and acknowledge its possible transition to oligarchy. [less ▲]

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See detailBlockchain as a driving force for federalism: A theory of cross-organizational task-technology fit
Roth, Tamara UL; Stohr, Alexander; Amend, Julia et al

in International Journal of Information Management (2022)

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See detailDeFi, Not So Decentralized: The Measured Distribution of Voting Rights
Barbereau, Tom Josua UL; Smethurst, Reilly UL; Papageorgiou, Orestis UL et al

in Proceedings of the Hawaii International Conference on System Sciences 2022 (2022, January)

Bitcoin and Ethereum are frequently promoted as decentralized, but developers and academics question their actual decentralization. This motivates further experiments with public permissionless ... [more ▼]

Bitcoin and Ethereum are frequently promoted as decentralized, but developers and academics question their actual decentralization. This motivates further experiments with public permissionless blockchains to achieve decentralization along technical, economic, and political lines. The distribution of tokenized voting rights aims for political decentralization. Tokenized voting rights achieved notoriety within the nascent field of decentralized finance (DeFi) in 2020. As an alternative to centralized crypto-asset exchanges and lending platforms (owned by companies like Coinbase and Celsius), DeFi developers typically create non-custodial projects that are not majority-owned or managed by legal entities. Holders of tokenized voting rights can instead govern DeFi projects. To scrutinize DeFi’s distributed governance strategies, we conducted a multiple-case study of non-custodial, Ethereum-based DeFi projects: Uniswap, Maker, SushiSwap, Yearn Finance, and UMA. Our findings are novel and surprising: quantitative evaluations of DeFi’s distributed governance strategies reveal a failure to achieve political decentralization. [less ▲]

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See detailThe Social Construction of Self-Sovereign Identity: An Extended Model of Interpretive Flexibility
Weigl, Linda UL; Barbereau, Tom Josua UL; Rieger, Alexander UL et al

in Proceedings of the 55th Hawaii International Conference on System Sciences (HICSS) (2022, January)

User-centric identity management systems are gaining momentum as concerns about Big Tech and Big Government rise. Many of these systems are framed as offering Self-Sovereign Identity (SSI). Yet, competing ... [more ▼]

User-centric identity management systems are gaining momentum as concerns about Big Tech and Big Government rise. Many of these systems are framed as offering Self-Sovereign Identity (SSI). Yet, competing appropriation and the social embedding of SSI have resulted in diverging interpretations. These vague and value-laden interpretations can damage the public discourse and risk misrepresenting values and affordances that technology offers to users. To unpack the various social and technical understandings of SSI, we adopt an ‘interpretive flexibility’ lens. Based on a qualitative inductive interview study, we find that SSI’s interpretation is strongly mediated by surrounding institutional properties. Our study helps to better navigate these different perceptions and highlights the need for a multidimensional framework that can improve the understanding of complex socio-technical systems for digital government practitioners, researchers, and policy-makers. [less ▲]

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See detailTowards an evaluation of incentives and nudges for smart charging
Marxen, Hanna UL; Chemudupaty, Raviteja UL; Graf-Drasch, Valerie et al

in Proceedings of the 30th European Conference on Information Systems (ECIS 2022) (2022)

Electric vehicles (EVs) are an important cornerstone to achieve transport decarbonization. Still, simultaneous charging of EVs when home charging increases peak demand, especially during evenings. Smart ... [more ▼]

Electric vehicles (EVs) are an important cornerstone to achieve transport decarbonization. Still, simultaneous charging of EVs when home charging increases peak demand, especially during evenings. Smart charging allows optimal distribution of load, thus preventing peak loads. Nevertheless, this incorporates certain risks for the EV user, e.g., unavailability of EVs for unplanned events. This might lead to a lack of user acceptance. This paper focuses on specific incentives and nudges, motivating users to adopt smart charging. We conducted an integrative literature review, bringing together literature from different areas. Possible incentives and nudges are monetary incentives, feedback, gamification, or smart charging as a default-setting. We conducted three focus groups with 13 EV users in Luxembourg to get first insights into which of those incentives and nudges they prefer. Preliminary results indicate that incentives and nudges should be individualized. In the future, we would use these first insights to develop a large-scale survey. [less ▲]

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See detailBenchmarking building energy performance: Accuracy by involving occupants in collecting data - A case study in Germany
Wederhake, Lars; Wenninger, Simon; Wiethe, Christian et al

in Journal of Cleaner Production (2022), 379

Energy performance certificates (EPC) aim to provide transparency about building energy performance (BEP) and benchmark buildings. Despite having qualified auditors examining buildings through on-site ... [more ▼]

Energy performance certificates (EPC) aim to provide transparency about building energy performance (BEP) and benchmark buildings. Despite having qualified auditors examining buildings through on-site visits, BEP accuracy in EPCs is frequently criticized. Qualified auditors are often bound to engineering-based energy quantification methods. However, recent studies have revealed data-driven methods to be more accurate regarding benchmarking. Unlike engineering methods, data-driven methods can learn from data that non-experts might collect. This raises the question of whether data-driven methods allow for simplified data collection while still achieving the same accuracy as prescribed engineering-based methods. This study presents a method for selecting building variables, which even occupants can reliably collect and which at the same time contribute most to a data-driven method's predictive power. The method is tested and validated in a case study on a real-world data set containing 25,000 German single-family houses. Having all data collected by non-experts, results show that the data-driven method achieves about 35% higher accuracy than the currently used engineering method by qualified auditors. Our study proposes a stepwise method to design data-driven EPCs, outlines design recommendations, and derives policy implications. [less ▲]

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See detailSystemic risks in electricity systems: A perspective on the potential of digital technologies
Körner, Marc-Fabian; Sedlmeir, Johannes UL; Weibelzahl, Martin et al

in Energy Policy (2022), 164

In the last decades, several developments have transformed electricity systems in Europe towards liberalized and decentralized systems that are coupled inter-sectorally and inter-regionally. These ... [more ▼]

In the last decades, several developments have transformed electricity systems in Europe towards liberalized and decentralized systems that are coupled inter-sectorally and inter-regionally. These developments have yielded various significant benefits, such as increased efficiency and robustness. However, we argue that they have also caused new interdependencies and complexity with a corresponding increase in associated systemic risks, e.g., local failures may spread faster and more extensively throughout the system. In this paper, we illustrate how systemic risks may arise in European electricity systems by discussing three exemplary developments. We also discuss the decisive role of the digital transformation that, on the one hand, speeds up the transition of electricity systems and challenges electricity systems’ stability through rapid change, but on the other hand may also provide solutions to tackle systemic risks. We argue that, especially in a strongly interconnected world, policymakers must implement a global perspective on these critical and increasingly complex systems, requiring adequate cooperation with respect to data. Using an exemplary case from Germany, we finally illustrate how an intensified data exchange may help to address systemic risks. In this context, we draw a perspective on the potential of emerging digital technologies, like self-sovereign identities, blockchains, and privacy-enhancing technologies. [less ▲]

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See detailThe transparency challenge of blockchain in organizations
Sedlmeir, Johannes UL; Lautenschlager, Jonathan; Fridgen, Gilbert UL et al

in Electronic Markets (2022), 32(3), 1779--1794

This position paper discusses the challenges of blockchain applications in businesses and the public sector related to an excessive degree of transparency. We first point out the types of sensitive data ... [more ▼]

This position paper discusses the challenges of blockchain applications in businesses and the public sector related to an excessive degree of transparency. We first point out the types of sensitive data involved in different patterns of blockchain use cases. We then argue that the implications of blockchains’ information exposure caused by replicated transaction storage and execution go well beyond the often-mentioned conflicts with the GDPR’s “right to be forgotten” and may be more problematic than anticipated. In particular, we illustrate the trade-off between protecting sensitive information and increasing process efficiency through smart contracts. We also explore to which extent permissioned blockchains and novel applications of cryptographic technologies such as self-sovereign identities and zero-knowledge proofs can help overcome the transparency challenge and thus act as catalysts for blockchain adoption and diffusion in organizations. [less ▲]

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See detailIntegration der Flexibilitätsvermarktung
Ahrens, Raphael; Köberlein, Jana; Bank, Lukas et al

in Energieflexibilität in der deutschen Industrie: Band 2 - Markt- und Stromsystem, Managementsysteme und Technologien energieflexibler Fabriken (DOI: https://doi.org/10.24406/publica-258) (2022)

Die Energiesynchronisationsplattform adressiert den gesamten Prozess des automatisierten Energieflexibilitätshandels von der Maschine bis zu den Vermarktungsservices. Sie stellt somit das übergeordnete ... [more ▼]

Die Energiesynchronisationsplattform adressiert den gesamten Prozess des automatisierten Energieflexibilitätshandels von der Maschine bis zu den Vermarktungsservices. Sie stellt somit das übergeordnete Gesamtkonzept eines digitalen Ökosystems dar, welches industrielle Nachfrageflexibilität ermöglicht. Die Energiesynchronisationsplattform besteht dabei aus unternehmensindividuellen Unternehmensplattformen und einer zentralen Marktplattform. Der Marktplattform kommt die Rolle der Servicevermittlung zu. Dies ermöglicht es, auf Veränderungen innerhalb der Services bzw. der Marktplattform schnell reagieren zu können. Im vorliegenden Kapitel werden beispielhafte Services der Unternehmens- und Marktplattformen beschrieben. Zudem wird ein Überblick über die Referenzabläufe für den Betrieb und die Vermarktung von Energieflexibilität gegeben. Die Prozesse werden anhand eines möglichen Anwendungsfalls dargestellt. Außerdem wird das weiterentwickelte Energieflexibilitätsdatenmodell vorgestellt und anhand von vier Klassen beschrieben. Zur Bedrohungsanalyse im Kontext der IT-Sicherheit werden Threat Models (Bedrohungsmodelle) angewandt und auf Basis verschiedener Sicherheitslevels vorgestellt. Darüber hinaus werden Rollen- und Rechtedefinitionen beschrieben und Anforderungen an die IT-Sicherheit abgeleitet. Eine Kurzvorstellung entwickelter Demonstratoren schließt das Kapitel ab. [less ▲]

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