10,667 research outputs found

    A coupled terrestrial and aquatic biogeophysical model of the Upper Merrimack River watershed, New Hampshire, to inform ecosystem services evaluation and management under climate and land-cover change

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    Accurate quantification of ecosystem services (ES) at regional scales is increasingly important for making informed decisions in the face of environmental change. We linked terrestrial and aquatic ecosystem process models to simulate the spatial and temporal distribution of hydrological and water quality characteristics related to ecosystem services. The linked model integrates two existing models (a forest ecosystem model and a river network model) to establish consistent responses to changing drivers across climate, terrestrial, and aquatic domains. The linked model is spatially distributed, accounts for terrestrial–aquatic and upstream–downstream linkages, and operates on a daily time-step, all characteristics needed to understand regional responses. The model was applied to the diverse landscapes of the Upper Merrimack River watershed, New Hampshire, USA. Potential changes in future environmental functions were evaluated using statistically downscaled global climate model simulations (both a high and low emission scenario) coupled with scenarios of changing land cover (centralized vs. dispersed land development) for the time period of 1980–2099. Projections of climate, land cover, and water quality were translated into a suite of environmental indicators that represent conditions relevant to important ecosystem services and were designed to be readily understood by the public. Model projections show that climate will have a greater influence on future aquatic ecosystem services (flooding, drinking water, fish habitat, and nitrogen export) than plausible changes in land cover. Minimal changes in aquatic environmental indicators are predicted through 2050, after which the high emissions scenarios show intensifying impacts. The spatially distributed modeling approach indicates that heavily populated portions of the watershed will show the strongest responses. Management of land cover could attenuate some of the changes associated with climate change and should be considered in future planning for the region

    Visions, Values, and Videos: Revisiting Envisionings in Service of UbiComp Design for the Home

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    UbiComp has been envisioned to bring about a future dominated by calm computing technologies making our everyday lives ever more convenient. Yet the same vision has also attracted criticism for encouraging a solitary and passive lifestyle. The aim of this paper is to explore and elaborate these tensions further by examining the human values surrounding future domestic UbiComp solutions. Drawing on envisioning and contravisioning, we probe members of the public (N=28) through the presentation and focus group discussion of two contrasting animated video scenarios, where one is inspired by "calm" and the other by "engaging" visions of future UbiComp technology. By analysing the reasoning of our participants, we identify and elaborate a number of relevant values involved in balancing the two perspectives. In conclusion, we articulate practically applicable takeaways in the form of a set of key design questions and challenges.Comment: DIS'20, July 6-10, 2020, Eindhoven, Netherland

    Hard Lessons about Philanthropy & Community Change from the Neighborhood Improvement Initiative

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    Between 1996 and 2006, the William and Flora Hewlett Foundation invested over $20 million in the Neighborhood Improvement Initiative (NII), an ambitious effort to help three neighborhoods in the Bay Area reduce poverty and develop new leaders, better services, more capable organizations, and stronger connections to resources. On some counts NII succeeded, and on others it struggled mightily. In the end, despite some important accomplishments, NII did not fulfill its participants' hopes and expectations for broad, deep, and sustainable community change. In those accomplishments and shortcomings, and in the strategies that produced them, however, lies a story whose relevance exceeds the boundaries of a single initiative. Our goal is to examine this story in the context of other foundation sponsored initiatives to see if it can help philanthropy support community change and other types of long-term, community-based initiatives more effectively.As we began to review materials and conduct interviews, we learned of NII's accomplishments in each neighborhood, including new organizations incubated, new services stimulated, and new leaders helped to emerge. We also quickly discovered multiple, and often conflicting, perspectives on NII's design, implementation, and outcomes that were hard to reconcile. Some of this Rashomon effect is to be expected in a complex, long-term community change initiative that evolves over time with changing players. Some can also be attributed to the different dynamics and trajectories in each of the three sites.We have tried to describe all points of view as accurately as possible without favoring any one perspective. Moreover, we have tried to look beyond the lessons drawn exclusively from NII and to position all of these varied opinions within a broader field-wide perspective, wherever possible.The frustrations of NII's participants and sponsors are mirrored in many other foundations' major initiatives. Indeed, our reviewers -- who have been involved in many such initiatives as funders, evaluators, technical assistance providers, and intermediaries -- all underscored how familiar they were with the challenges and pitfalls described here, both those related specifically to community change efforts and those pertinent to other initiatives. Because the opportunity to discuss the frustrations candidly has been limited, however, they often are relegated to concerns expressed sotto voce. So it was particularly important throughout the review to solicit from our interviewees ideas or suggestions for improving their work together. We offer these along with our own observations as a way to stimulate further reflection and debate, because we believe that philanthropy has an important role to play in improving outcomes for poor communities and their residents. Few foundations have been willing to contribute to this level of honest and sometimes painful public dialogue. But by commissioning this retrospective analysis, the Hewlett Foundation demonstrates a desire to help the field learn and move forward, and we applaud that

    Cyber-crime Science = Crime Science + Information Security

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    Cyber-crime Science is an emerging area of study aiming to prevent cyber-crime by combining security protection techniques from Information Security with empirical research methods used in Crime Science. Information security research has developed techniques for protecting the confidentiality, integrity, and availability of information assets but is less strong on the empirical study of the effectiveness of these techniques. Crime Science studies the effect of crime prevention techniques empirically in the real world, and proposes improvements to these techniques based on this. Combining both approaches, Cyber-crime Science transfers and further develops Information Security techniques to prevent cyber-crime, and empirically studies the effectiveness of these techniques in the real world. In this paper we review the main contributions of Crime Science as of today, illustrate its application to a typical Information Security problem, namely phishing, explore the interdisciplinary structure of Cyber-crime Science, and present an agenda for research in Cyber-crime Science in the form of a set of suggested research questions

    Land system science and sustainable development of the earth system: A global land project perspective

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    Land systems are the result of human interactions with the natural environment. Understanding the drivers, state, trends and impacts of different land systems on social and natural processes helps to reveal how changes in the land system affect the functioning of the socio-ecological system as a whole and the tradeoff these changes may represent. The Global Land Project has led advances by synthesizing land systems research across different scales and providing concepts to further understand the feedbacks between social-and environmental systems, between urban and rural environments and between distant world regions. Land system science has moved from a focus on observation of change and understanding the drivers of these changes to a focus on using this understanding to design sustainable transformations through stakeholder engagement and through the concept of land governance. As land use can be seen as the largest geo-engineering project in which mankind has engaged, land system science can act as a platform for integration of insights from different disciplines and for translation of knowledge into action

    Resilience trinity: safeguarding ecosystem functioning and services across three different time horizons and decision contexts

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    Ensuring ecosystem resilience is an intuitive approach to safeguard the functioning of ecosystems and hence the future provisioning of ecosystem services (ES). However, resilience is a multi‐faceted concept that is difficult to operationalize. Focusing on resilience mechanisms, such as diversity, network architectures or adaptive capacity, has recently been suggested as means to operationalize resilience. Still, the focus on mechanisms is not specific enough. We suggest a conceptual framework, resilience trinity, to facilitate management based on resilience mechanisms in three distinctive decision contexts and time‐horizons: 1) reactive, when there is an imminent threat to ES resilience and a high pressure to act, 2) adjustive, when the threat is known in general but there is still time to adapt management and 3) provident, when time horizons are very long and the nature of the threats is uncertain, leading to a low willingness to act. Resilience has different interpretations and implications at these different time horizons, which also prevail in different disciplines. Social ecology, ecology and engineering are often implicitly focussing on provident, adjustive or reactive resilience, respectively, but these different notions of resilience and their corresponding social, ecological and economic tradeoffs need to be reconciled. Otherwise, we keep risking unintended consequences of reactive actions, or shying away from provident action because of uncertainties that cannot be reduced. The suggested trinity of time horizons and their decision contexts could help ensuring that longer‐term management actions are not missed while urgent threats to ES are given priority

    Applicability and Challenges of Deep Reinforcement Learning for Satellite Frequency Plan Design

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    The study and benchmarking of Deep Reinforcement Learning (DRL) models has become a trend in many industries, including aerospace engineering and communications. Recent studies in these fields propose these kinds of models to address certain complex real-time decision-making problems in which classic approaches do not meet time requirements or fail to obtain optimal solutions. While the good performance of DRL models has been proved for specific use cases or scenarios, most studies do not discuss the compromises and generalizability of such models during real operations. In this paper we explore the tradeoffs of different elements of DRL models and how they might impact the final performance. To that end, we choose the Frequency Plan Design (FPD) problem in the context of multibeam satellite constellations as our use case and propose a DRL model to address it. We identify 6 different core elements that have a major effect in its performance: the policy, the policy optimizer, the state, action, and reward representations, and the training environment. We analyze different alternatives for each of these elements and characterize their effect. We also use multiple environments to account for different scenarios in which we vary the dimensionality or make the environment nonstationary. Our findings show that DRL is a potential method to address the FPD problem in real operations, especially because of its speed in decision-making. However, no single DRL model is able to outperform the rest in all scenarios, and the best approach for each of the 6 core elements depends on the features of the operation environment. While we agree on the potential of DRL to solve future complex problems in the aerospace industry, we also reflect on the importance of designing appropriate models and training procedures, understanding the applicability of such models, and reporting the main performance tradeoffs
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