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Effect of food value-chain connections on land-use change
Get PDFChanges in food production, often driven by distant demand, have a significant influence on sustainable management and use of land and water, and are in turn a driving factor of biodiversity change. While the connection between land use and demand through value chains is increasingly understood, there is no comprehensive conceptualisation of this relationship. To address this gap, we propose a conceptual framework and use it as a basis for a systematic review to characterise value-chain connection and explore its influence on land-use and -cover change. Our search in June 2022 on Web of Science and Scopus yielded 198 documents, describing studies completed after the year 2000 that provide information on both value-chain connection and land-use or -cover change. In total, we used 531 distinct cases to assess how frequently particular types of land-use or -cover change and value-chain connections co-occurred, and synthesized findings on their relations. Our findings confirm that 1) market integration is associated with intensification; 2) land managers with environmental standards more frequently adopt environmentally friendly practices; 3) physical and value-chain distances to consumers play a crucial role, with shorter distances associated with environmentally friendly practices and global chains linked to intensification and expansion. Incorporating these characteristics in existing theories of land-system change, would significantly advance understanding of land managers’ decision-making, ultimately guiding more environmentally responsible production systems and contributing to global sustainability goals.</p
Mobility chameleons:The current and potential users of shared micromobility
Get PDFBike and e-scooter sharing schemes are an emerging addition to modern urban mobility systems. The research aims to identify the mobility and sociodemographic user profile of bike and e-scooter sharing and understand the key determinants of people’s intention to use these modes in the future. To consider the effect of local context on shared micromobility usage, the study exploited survey data (N = 1607) that were collected in three European urban areas (Brussels, Munich, and Vienna). The obtained dataset provided information on respondents’ socioeconomic characteristics, mobility capabilities and preferences, including travel frequency by bike and e-scooter sharing services. The survey also collected information on respondents’ likelihood of travelling by shared micromobility in the future. The profile of current users was revealed by conducting a Latent Class Analysis (LCA). The measurement and membership LCA models were estimated based on the mobility and sociodemographic data, respectively. The three-class LCA model uncovered that shared micromobility users are mostly members of the so-called “Mobility chameleons” population group whereas few users belong to the “Car lovers” and the “Public transport fans” classes. Mobility chameleons travel by private, public, and shared modes, as well as by both motorized and active modes. Males, with medium and high income, who own a smartphone, dominate this group. Although mobility chameleons are present in all study areas, their share in the population varies. Regarding potential future usage, people’s willingness to travel by shared micromobility in the future is much higher than the present usage levels captured. Modelling the potential demand revealed that while many factors similarly influence the likelihood of travelling by bike and e-scooter sharing, the significance and strength of the effects vary for the two modes. The present research findings provide relevant input for modelling as well as predicting shared micromobility usage
The VerifyThis Collaborative Long-Term Challenge Series
Get PDFWe give a brief overview of the VerifyThis long-term challenge series. Goal of these challenges is to demonstrate practical value of formal methods, to evaluate the current tools on specifying and verifying requirements of realistic software systems, and to bring together the community for an exchange on the state-of-the-art and future directions. An emphasis is placed on encouraging collaboration between participating research groups, not just at a conceptual level but also towards integrating verification tools and approaches, e.g., sharing technical artifacts such as specifications and proofs. Website: https://verifythis.github.io/ Mailing List: [email protected]</p
Tools at the Frontiers of Quantitative Verification:QComp 2023 Competition Report
Get PDFThe analysis of formal models that include quantitative aspects such as timing or probabilistic choices is performed by quantitative verification tools. Broad and mature tool support is available for computing basic properties such as expected rewards on basic models such as Markov chains. Previous editions of QComp, the comparison of tools for the analysis of quantitative formal models, focused on this setting. Many application scenarios, however, require more advanced property types such as LTL and parameter synthesis queries as well as advanced models like stochastic games and partially observable MDPs. For these, tool support is in its infancy today. This paper presents the outcomes of QComp 2023: a survey of the state of the art in quantitative verification tool support for advanced property types and models. With tools ranging from first research prototypes to well-supported integrations into established toolsets, this report highlights today’s active areas and tomorrow’s challenges in tool-focused research for quantitative verification.</p
Qualifier document: Data Driven Smart Maintenance from theory to implementation
Get PDFThere has been a lot of focus within the Dutch Defence in recent years on smarter maintenance of (weapon) systems. This aligns with the desire for more Information-driven Operations (IGO) and is facilitated by the increasingly presence of sensors and data recorders in (weapon) systems. Additionally, it can help address challenges related to smaller crews on naval vessels, scarcityof technical personnel, and the desired higher readiness of equipment because of the current concerning developments in the world. Based on the Vision of the Dutch Defence, visions and roadmaps have been developed within various departments for the transition to (more) predictive maintenance. Predictive Maintenance and Logistics are also focal points within the Defence Data Science and AI strategy [1], with an accompanying developed roadmap. However, it has been observed that this transition is a challenging process, requiring the resolution of numerous underlying challenges. Moreover, full Predictive Maintenance is the ultimate goal, which may only be achieved in about 10 years,but there are also more achievable interim steps, such as automatic fault detection, automated diagnosis, and (on-board) health assessments of systems. This vision resulted in the development of the “Data Driven Smart Maintenance (DDSM)” project. In current literature numerous Artificial Intelligence (AI) models and emerging technologies exhibit promising capabilities in facilitating DDSM [2]. However, the seamless implementation of these AI models and especially Predictive Maintenance (PdM) with real-world data poses inherent chal-lenges [3]. Tiddens, et al. [4] found that companies often have a high ambition level of preventive maintenance but that this level is not feasible because of, for instance, the lack of data. There is a gap in the current literature regarding the different problems companies have with implementing DDSM. The discussion above shows the need for DDSM but it also shows that there are several problems with the implementation. Currently there is no clear view on what problems occur when companies try to implement DDSM. Especially the big difference between research on DDSM and the implementation of it is concerning. This concern calls for more research towards the problemsand issues there are regarding the implementation of DDSM. After identifying these problems, the focus can be shifted to solving them
ASO Author Reflections:Sentinel Lymph Node Biopsy for Patients with a Non-classic Lobular Carcinoma In Situ Breast Biopsy
Get PDFWatt-class silicon photonics-based optical high-power amplifier
Get PDFHigh-power amplifiers are critical components in optical systems spanning from long-range optical sensing and optical communication systems to micromachining and medical surgery. Today, integrated photonics with its promise of large reductions in size, weight and cost cannot be used in these applications, owing to the lack of on-chip high-power amplifiers. Integrated devices severely lack in output power owing to their small size, which limits their energy storage capacity. For the past two decades, large mode area (LMA) technology has played a disruptive role in fibre amplifiers, enabling a dramatic increase of output power and energy by orders of magnitude. Owing to the ability of LMA fibres to support significantly larger optical modes, the energy storage and power handling capabilities of LMA fibres have significantly increased. Therefore, an LMA device on an integrated platform can play a similar role in power and energy scaling of integrated devices. In this work, we demonstrate LMA waveguide-based watt-class high-power amplifiers in silicon photonics with an on-chip output power exceeding ~1 W within a footprint of only ~4.4 mm2. The power achieved is comparable and even surpasses that of many fibre-based amplifiers. We believe that this work has the potential to radically change the integrated photonics application landscape, allowing power levels previously unimaginable from an integrated device to replace much of today’s benchtop systems. Moreover, mass producibility, reduced size, weight and cost will enable yet unforeseen applications of laser technology
Special issue on:“Emerging industrial Digitalisation and machine learning applications in maintenance engineering, asset, and operations management”
Get PDFA front-tracking immersed-boundary framework for simulating Lagrangian melting problems
Get PDFIn so-called Lagrangian melting problems, a solid immersed in a fluid medium is free to rotate and translate in tandem with its phase-change from solid to liquid. Such configurations may be classified as a fluid-solid interaction (FSI) problem coupled to phase-change. Our present work proposes a numerical method capable of simulating these Lagrangian melting problems and adopts a front-tracking immersed-boundary (IB) method. We use the moving least squares IB framework, a well-established method for simulating a diverse range of FSI problems [1,2] and extend this framework to accommodate melting by additionally imposing the Stefan condition at the interface. In the spirit of canonical front-tracking methods, the immersed solid is represented by a discrete triangulated mesh which is separate from the Eulerian mesh in which the governing flow equations are solved. A known requirement for these methods is the need for comparable Eulerian and Lagrangian grid spacings to stabilise interpolation and spreading operations between the two grids. For a melting object, this requirement is inevitably violated unless interventional remeshing is introduced. Our work therefore presents a novel dynamic remeshing procedure to overcome this. The remeshing is based on a gradual coarsening of the triangulated Lagrangian mesh and amounts to a negligible computational burden per timestep owing to the incremental and local nature of its operations, making it a scalable approach. Moreover, the coarsening is coupled to a volume-conserving smoothing procedure detailed by Kuprat et al. [3], ensuring a zero net volume change in the remeshing step to machine precision. This added feature makes our present method highly specialised to the study of melting problems, where precise measurements of the melting solid's volume is often the primary predictive quantity of interest.</p
The development of scour holes in lowland rivers: a review on the hydrodynamic and geotechnical conditions
No full textScour holes are common features in lowland rivers. They can have significant depths and steep slopes which may threaten the stability of infrastructure. Therefore, understand-ing the dominant conditions that control the development of scour holes is essential. Previous studies mainly focused on the hydrodynamic conditions (i.e., flood events, channel geometry, and presence of a structure) that induce the formation of a scour hole. However, more recent research illustrated that the formation of a large group of scour holes cannot be explained by hydrodynamic conditions solely. The geotechnical conditions (i.e., the subsurface composition) significantly in-fluence the location of a scour hole, as it reflects the local susceptibility of the bed to erosion. Yet, the hydrodynamic and geotechnical conditions are mainly isolated in scour hole analysis. This review provides an overview of the drivers of the formation and migration of scour holes focusing on the interplay of hydrodynamic and geotechnical conditions