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Restructuring material thinking : Material and Data in Architecture and Urban Scales
No full textDigital data is becoming increasingly important in relation to building materials and materials in architecture and urban planning. In six chapters, the four experts Michael Hensel, Bob Geldermans, Defne Sunguroğlu Hensel, and Milica Vujovic cover the spectrum from data and materials to the question of availability and industrial production, artificial intelligence, and the Internet of Things with scientifically sound contributions. They show how it is possible to find tailor-made solutions to urgent questions such as building material interactions, ageing processes, circularity, urban mining, and global needs with advancing digitalization.
Digital tools for the optimization of installed material
Ageing, combination, circularity, and urban mining
A scientifically sound overvie
Cruel optimism in edtech: When the digital data practices of educational technology providers inadvertently hinder educational equity
No full textAs digital data become increasingly central to education, hopes for educational equity are pinned more strongly on educational technology providers. This paper examines the data practices of edtech providers who are not simply making token gestures towards justice and equality. Drawing on ethnographic interviews and Berlant’s notion of cruel optimism, it presents three data stories: (i) generating data to close the achievement gap, (ii) protecting data to ensure student privacy and (iii) using data to expose inequities. The paper suggests that datafication in education provides a showcase of cruel optimism, i.e., when the object of desire is blocking one’s flourishing. The conclusion considers the constitutive paradoxes of datafied education, and implications for education in the current phase of edu-technical transformation
Understanding the Marriage–Cohabitation Gap in Income Pooling: Evidence from 29 European Countries
No full textPooling all incomes was long seen as the norm in male-breadwinner marriages, but in a time of dual-earner families, cohabitation, and divorce, the underpinnings of this model are eroding. What consequences does this have for income pooling?
We compare ca. 130,000 married and cohabiting couples from 29 European countries in the 2010 European Union Survey of Income and Living Conditions (EU-SILC) via random effects logit models. We show that cohabiting couples are generally more likely than married couples to keep at least some income separately, the so-called cohabitation gap. Roughly a fifth of this gap we can attribute to compositional differences between married and cohabiting couples. Further, the cohabiting group is heterogeneous and smaller when comparing only couples with children or only couples with a long relationship duration. Lastly, we show that there is substantial variation in the size of the cohabitation gap across countries. The size of this gap varies with the country-specific cohabitation rate, divorce rate, and female labor force participation rate. While there is considerable heterogeneity among cohabiting couples, married and cohabiting couples remain distinct in their resource-sharing behavior. Income pooling does not become more comparable when cohabitation, marital instability, and women’s economic independence become more widespread in the broader society. Our study reconciles disparate findings of previous cross-national research on the cohabitation gap
Geopolymer Concrete: Advancements in Performance and Sustainability
No full textGeopolymer Concrete: Advancements in Performance and Sustainability is a thorough guide on a research topic in which incremental progress has been made in recent years. To contribute to the extensive investigations into the different aspects of this eco-friendly building material, the editors have selected experts from across the globe, aiming to reflect the worldwide interest shown by the research community.
The book opens with fundamental information, such as properties and production (both design and manufacturing techniques). It then includes various applications and useful LCA analysis. Recent advances with particular focus on improvements in durability, strength, and thermal performance are discussed next, with valuable data supplied by real-world case studies. Considerations related to the material’s environmental impact, challenges and barriers to its adoption, and other insights into current standards and regulations conclude the coverage.
This multifaceted resource serves not only as a unique source of information for readers in academia as well as industry seeking to stay current in their field but may also prove to be worthwhile reading for those professionals responsible for better and more sustainable construction enterprises
Construction and spectrum of the AndersonHamiltonian with white noise potential on ℝ2 and ℝ3
No full textWe propose a simple construction of the Anderson Hamiltonian with white noise potential on R² and R³ based on the solution theory of the parabolic Anderson model. It relies on a theorem of Klein and Landau (1981) that associates a unique self-adjoint generator to a symmetric semigroup satisfying some mild assumptions. Then, we show that almost surely the spectrum of this random Schrödinger operator is R. To prove this result, we extend the method of Kotani (1985) to our setting of singular random operators
How binary oxidic overlayers influence the thermochemical stability and surface morphology of (La,Sr)CoO3-δ
No full textModifying mixed ionic and electronic conductor (MIEC) surfaces has gained attention as a strategy to enhance oxygen exchange reaction kinetics and attenuate surface degradation. This study investigates the high-temperature stability and cation segregation behavior of La0.6Sr0.4CoO3-δ (LSC) thin films modified with ∼0.5 nm CaO and SnO2 overlayers after annealing at 800 °C. Combining Time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS), Secondary electron microscopy (SEM)/Energy dispersive X-ray analysis (EDX), and Auger-Meitner electron spectroscopy (AMES), we provide a comprehensive picture of surface and sub-surface changes, segregation, interdiffusion, and secondary phase formation. Our results show that Sr enrichment during high-temperature annealing occurs at the surface regardless of the overlayer. However, significant differences in surface morphology emerge depending on the overlayer. Our results indicate that surface acidity, modulated by the oxide overlayer, is of fundamental importance for the formation of secondary phases and determines the interaction with acidic gas-phase impurities. These findings suggest that surface modifications are not a viable strategy to prevent Sr segregation at high temperatures. However, they can lead to complicated surface dynamics and significantly change the secondary phase formation processes induced by Sr segregation
Exploring the potential of Sufficiency scenarios to reach Net-Zero buildings in Swiss municipalities
Get PDFDespite the prioritisation of energy efficiency measures and renewable energy integration for decarbonising the building and construction sector, technology-centric approaches in Swiss national energy strategies have exhibited limitations in curtailing both operational and embodied carbon emissions over the past decade. The absence of defined resource consumption boundaries within the building sector for existing buildings presents a significant challenge not only in Switzerland but globally. This study investigates the implementation of sufficiency principles within the Swiss building sector offering insights highly relevant to the broader European context as a potential mitigation strategy, as also recognised by the IPCC. The impact of various sufficiency and efficiency measures (e.g. promote shared living, renovation of building envelope) is quantitatively evaluated through different scenarios. Principal component analysis (PCA) and k-medoids clustering is applied on a comprehensive dataset encompassing existing building stock characteristics and socio-demographic information across all 508 Swiss urban municipalities. Specifically, the scenarios assess the efficacy of sufficiency-based measures in reducing emissions from the existing residential building stock eligible for renovation until 2050. The findings indicate that while sufficiency and efficiency measures applied in isolation result in only modest emission reductions, a strategically targeted combination of space demand reduction and renovation offers significant potential to lower both operational and embodied emissions helping to close the CO₂ gap and reduce reliance on the uncertain future development of carbon removal and renewable energy technologies. Furthermore, this research derives policy recommendations, informed by the analysed scenarios and complimented with the existing Swiss building policy landscape, to support the development of future cantonal energy and carbon policies
SKYLINK: Scalable and Resilient Link Management in LEO Satellite Networks
No full textThe rapid growth of space-based services has established Low Earth Orbit (LEO) satellite networks as a promising option for global broadband connectivity. Next-generation LEO networks leverage inter-satellite links (ISLs) to provide faster and more reliable communications compared to traditional bent-pipe architectures, even in remote regions. However, the high mobility of satellites, dynamic traffic patterns, and potential link failures pose significant challenges for efficient and resilient routing. To address these challenges, we model the LEO satellite network as a time-varying graph comprising a constellation of satellites and ground stations. Our objective is to minimize a weighted sum of average delay and packet drop rate. Each satellite independently decides how to distribute its incoming traffic to neighboring nodes in real time. Given the infeasibility of finding optimal solutions at scale, due to the exponential growth of routing options and uncertainties in link capacities, we propose SKYLINK, a novel fully distributed learning strategy for link management in LEO satellite networks. SKYLINK enables each satellite to adapt to the time-varying network conditions, ensuring real-time responsiveness, scalability to millions of users, and resilience to network failures, while maintaining low communication overhead and computational complexity. To support the evaluation of SKYLINK at global scale, we develop a new simulator for large-scale LEO satellite networks. For 25.4 million users, SKYLINK reduces the weighted sum of average delay and drop rate by 29% compared to the bent-pipe approach, and by 92% compared to Dijkstra. It lowers drop rates by 95% relative to k-shortest paths, 99% relative to Dijkstra, and 74% compared to the bent-pipe baseline, while achieving up to 46% higher throughput. At the same time, SKYLINK maintains constant computational complexity with respect to constellation size
The HESTIA Framework : From an Internet of Things to an Internet of Meaning
No full textAt first glance, the Internet of Things brings about an expectation for users (be it individuals or organizations) to interact with the many Internet-connected “things” in a natural way while also enhancing everyday work and life. The emergence of smart cities, and smart homes, also fuels the need for a broad audience to interact with the Internet of Things in a natural way. In current practice, however, users are confronted with the need to negotiate a complex landscape involving a myriad of protocols, standards, and work-arounds to integrate “legacy” devices, etc. We contend that users should not have to think about their world in terms of specific sensors, actuators, gateways, and protocols but rather in terms of room temperatures, the desire to increase the temperature in the living room, the concern that the plants in the garden are watered on time, etc. This creates a need to bridge this gap by creating a semantically meaningful layer of abstraction on top of the sensors and actuators that make up the “device and protocols oriented” Internet of Things, to create an Internet of Meaning. To this end, this chapter reports on the HESTIA framework, which combines: (1) An abstraction of the implementation details pertaining to, e.g., different protocols, standards, etc. (2) A domain-specific (conceptual) modeling framework in terms of which “things” can be captured in a way that is meaningful to the domain at hand (3) Based on this, a domain-specific language that is understandable by the user, enabling users to define control/behavioral rules in terms that are meaningful to them The presented HESTIA framework will be illustrated in terms of examples in the context of home and garden automation. Though such application contexts seem less challenging and complex than industrial Internet of Things applications, the variety of devices and protocols and distance between users and the technical details are often larger than in the case of industrial Internet of Things
Applying a novel scoring approach to assess the success of waste management CDM projects by region, size, and subtype
Get PDFGreenhouse gas emission abatement is a primary objective of the Clean Development Mechanism (CDM) of the United Nations Framework Convention on Climate Change (UNFCCC) under the Kyoto Protocol. In this study, three criteria were developed and ascribed to CDM projects under sectoral scope 13, “waste handling and disposal”: 1) project performance; 2) specific costs for issued certified emission reductions (CERs); and 3) transition status to the Paris Agreement Crediting Mechanism (PACM) or a voluntary carbon offsetting program. Using the criteria and a success threshold, an aggregate scoring system was devised to rate the overarching “success” of each individual project. Finally, the projects were grouped by geographic subregion, project subtype, and size classification to observe success rate differences. Of 280 projects evaluated, only 114 were assessed as being successful under this model (40.7 %). Projects in “Latin America and the Caribbean” were more than 1.5 times more likely to be evaluated as successful as projects in “Southeast Asia” and “Mainland Asia”. Projects classified as “large” were 1.8 times more likely to be evaluated as successful compared to projects classified as “small”. Projects managing “manure”, “landfill power”, and “landfill flaring” were more likely to be evaluated as successful as “waste water” projects. The evaluation also showed that amongst the chosen criteria, cost-effectiveness is the least critical criterion for the success and longevity of the CDM projects. The developed novel scoring method provides a useful tool to assess the general project performance of CDM projects and could also be applied to other sectoral scopes