86 research outputs found

    Structure-property relationships in glass-reinforced polyamide, part 1: The effects of fiber content

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    We present the results of an extensive study of the performance of injection-molded glass-fiber reinforced polyamide 66 with glass content between 0 and 40% and based on two chopped glass products both sized with polyamide compatible sizing. Mechanical properties generally improved with increasing glass content, modulus linearly, strength with a maximum at 40-50% glass content, and impact showing an initial decrease from the resin value with a minimum at 4% glass content before increasing at higher glass contents. Residual fiber length decreased linearly with increasing glass content. Interfacial strength was found to be in the range of 30-36 MPa, and no significant differences in dry as molded performance was found between the 123D and 173X sizings. Conditioning these composites in either boiling water or water/glycol mixtures leads to a dramatic drop in both tensile modulus and tensile strength. This is most likely due to the high level of matrix plasticization. After conditioning, the 173X sized glass delivered a significantly higher level of tensile elongation at all fiber contents. Excellent agreement was obtained between the experimental data and the theoretical predictions of the rule of mixtures model for modulus and the Kelly-Tyson model for strength over the range of fiber concentrations studied

    Detection of change in land surface properties using space-born images

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    Effectively empowering: A different look at bolstering the effectiveness of global environmental assessments

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    Global environmental assessments are widely considered to play a prominent role in environmental governance. However, they are also criticised for a lack of effectiveness in informing policy and decision-making. In response, GEAs have adopted a number of strategies to bolster their effectiveness, including by orienting themselves towards solutions (solution-orientation), increasing the diversity of included experts (participation), and producing more targeted assessments (contextualisation). In this article, we analyse these strategies as attempts to be effective for multiple audiences while also identifying the limitations of these strategies. Based on this analysis, we propose to conceive of GEAs as processes that are able to empower diverse actors – ranging from diplomats in international negotiations to civil society activists, or indigenous and local knowledge holders – to act towards socio-environmental objectives. Seen in this light, the effectiveness of GEAs can be improved by reflecting on which actors can benefit from assessments and how assessments can contribute to their empowerment. This strategy goes beyond current proposals that aim to strengthen the authority of assessments by boosting the scientific quality and credibility of the reports. Indeed, it complements them with an explicitly political perspective. Using examples of empowerment in different phases of GEA production and use, we argue that this reconceptualisation of effectiveness requires assessments to reflect a diversity of problem and solution frames, thereby creating entry points for the empowerment of a broad range of actors. We conclude by providing three illustrative ideas to improve effectiveness for the design and execution of assessments

    Catalyzing change: a literature review on the implementation of the Nature Futures Framework

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    The Nature Futures Framework (NFF), developed under the Intergovernmental Science–Policy Platform on Biodiversity and Ecosystem Services (IPBES), serves as a catalyst for advancing new scenarios and models focused on biodiversity and ecosystem services within the broader research community. In particular, the framework facilitates the development of scenarios and models that can help guide change processes toward desirable futures for nature and people. This paper assesses 31 studies that have engaged with the NFF since its introduction in 2020, aiming to identify which research areas have been addressed, and where development needs remain. The applications exhibit a large diversity in terms of locations, spatial scales, methods, outputs, and stakeholder involvement. The most common use of the framework has been in developing visions and scenarios. Nearly all studies engaged with diverse values of nature through the framework’s fundamental value perspectives: ‘ Nature for Society ’, ‘ Nature for Natur e’, and ‘ Nature as Culture / One with Nature ’. While the framework is generally perceived as useful, challenges remain in integrating the NFF across multiple scales and fully incorporating plural values, particularly in measuring relational aspects and avoiding Western-centric biases. Future research priorities include developing integrated, quantitative studies and exploring transformative pathways to enhance the framework's effectiveness in driving sustainable outcomes. Overall, the growing body of work using the NFF provides a strong foundation for distilling best practices, facilitating large-scale applications, and achieving the framework's objectives

    Bringing the Nature Futures Framework to life: creating a set of illustrative narratives of nature futures.

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    UNLABELLED: To halt further destruction of the biosphere, most people and societies around the globe need to transform their relationships with nature. The internationally agreed vision under the Convention of Biological Diversity-Living in harmony with nature-is that "By 2050, biodiversity is valued, conserved, restored and wisely used, maintaining ecosystem services, sustaining a healthy planet and delivering benefits essential for all people". In this context, there are a variety of debates between alternative perspectives on how to achieve this vision. Yet, scenarios and models that are able to explore these debates in the context of "living in harmony with nature" have not been widely developed. To address this gap, the Nature Futures Framework has been developed to catalyse the development of new scenarios and models that embrace a plurality of perspectives on desirable futures for nature and people. In this paper, members of the IPBES task force on scenarios and models provide an example of how the Nature Futures Framework can be implemented for the development of illustrative narratives representing a diversity of desirable nature futures: information that can be used to assess and develop scenarios and models whilst acknowledging the underpinning value perspectives on nature. Here, the term illustrative reflects the multiple ways in which desired nature futures can be captured by these narratives. In addition, to explore the interdependence between narratives, and therefore their potential to be translated into scenarios and models, the six narratives developed here were assessed around three areas of the transformative change debate, specifically, (1) land sparing vs. land sharing, (2) Half Earth vs. Whole Earth conservation, and (3) green growth vs. post-growth economic development. The paper concludes with an assessment of how the Nature Futures Framework could be used to assist in developing and articulating transformative pathways towards desirable nature futures. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11625-023-01316-1

    Report On The Workshop ‘Global Modelling Of Biodiversity And Ecosystem Services’

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    A three-day workshop on ‘Global Modelling of Biodiversity and Ecosystem Services’, was held in the Hague, Netherlands, from 24th to 26th June 2019. The workshop, attended by 35 modelling and scenario-building experts, was organised on behalf of the former IPBES 1 expert group on scenarios and models of the first IPBES work programme by its interim technical support unit, and hosted by the PBL Netherlands Environmental Assessment Agency. The workshop drew on the ‘nature futures’ participatory scenario-building exercise initiated by the IPBES expert group on scenarios and models, and other biodiversity modelling initiatives such as the ISIMIP project 2 working on adding biodiversity to the Shared Socioeconomic Pathways (SSPs) scenarios framework, the'bending the curve'initiative 3 led by IIASA 4 and WWF 5, and GEOBON 6 working on modelling Essential Biodiversity Variables. The workshop was a step towards coordinating across biodiversity modelling initiatives, to build on each other’s work, and to seek synergies for the production of innovative scenarios on biodiversity and ecosystem services to inform the post-2020 agenda of the Convention on Biological Diversity, as well as the Sustainable Development Goal

    Developing multiscale and integrative nature–people scenarios using the Nature Futures Framework

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    1. Scientists have repeatedly argued that transformative, multiscale global scenarios are needed as tools in the quest to halt the decline of biodiversity and achieve sustainability goals. 2. As a first step towards achieving this, the researchers who participated in the scenarios and models expert group of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) entered into an iterative, participatory process that led to the development of the Nature Futures Framework (NFF). 3. The NFF is a heuristic tool that captures diverse, positive relationships of humans with nature in the form of a triangle. It can be used both as a boundary object for continuously opening up more plural perspectives in the creation of desirable nature scenarios and as an actionable framework for developing consistent nature scenarios across multiple scales. 4. Here we describe the methods employed to develop the NFF and how it fits into a longer term process to create transformative, multiscale scenarios for nature. We argue that the contribution of the NFF is twofold: (a) its ability to hold a plurality of perspectives on what is desirable, which enables the development of joint goals and visions and recognizes the possible convergence and synergies of measures to achieve these visions and (b), its multiscale functionality for elaborating scenarios and models that can inform decision-making at relevant levels, making it applicable across specific places and perspectives on nature. 5. If humanity is to achieve its goal of a more sustainable and prosperous future rooted in a flourishing nature, it is critical to open up a space for more plural per- spectives of human–nature relationships. As the global community sets out to de- velop new goals for biodiversity, the NFF can be used as a navigation tool helping to make diverse, desirable futures possible
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