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Creators/Authors contains: "Donovan, S"

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  1. null (Ed.)
    Relic charcoal hearths (RCHs) have produced distinct legacy effects in forest soils around the world. Recently, LiDAR imagery has revealed thousands of 18th–early 20th century RCHs in Litchfield County, Connecticut, USA; however, the effects of RCHs on a landscape-scale are not well-documented, particularly fine-scale heterogeneity within RCHs and surrounding soils. This study examines the long-term impacts of charcoal production by measuring RCH soil chemical and physical properties from three perspectives: (1) compared to adjacent reference sites (RSadj), (2) laterally at systematic distances away from the RCH center, and (3) vertically within the RCH soil profile. Mean charcoal abundance was greater in RCH sites than RSadj (p < 0.01). Soil organic carbon (SOC), total C, and extractable Ca2+, Mg2+, Na+ were greater in RCH sites as compared to RSadj (p < 0.01), and available phosphorus (p < 0.01), K+, and trace elements (Mo, Ag, Hg, and Se) were lower (p < 0.05). In vertical profiles, many RCHs had 2 charcoal-rich layers within the anthropic epipedon, demonstrating multiple episodes of charcoal production. Peaks in SOC, C:N, Ca2+, Mg2+ corresponded with charcoal-rich layers. Systematic transect sampling across the RCH boundary identified charcoal fragments in soils at distances up to 25 m beyond the RCH boundary, increasing the surface-level (0–15 cm) area of impact for an individual RCH by more than 30×, from a 5-m radius (RCH area = 78.5 m2) to a 30-m radius (total area of impact = 2826 m2). These findings capture fine-scale variations within and among RCH and reference sites and contribute to estimating the total area of forest soils impacted by historical charcoal production. 
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  2. It can take a domain scientist weeks to set up a circuit, meeting for hours with IT administrators to figure out exactly what is needed, approvals from their own campus along with the remote campuses to set up a simple circuit to transfer data between campuses on an ongoing basis. Talking about networks may as well be a foreign language to many domain scientists. As such, we need to make it easier for domain scientists to allocate and configure resources for scientific applications without needing to understand the details of bandwidth, circuits, and port numbers. This session will discuss the challenges in supporting domain science applications across long distances and multiple management domains. We will discuss the AtlanticWave/SDX project and how it approaches this problem, making it possible for a domain scientist with little networking know-how to create paths across an intercontinental network while making network administrators' lives easier in the process. We will focus on the tools being developed to manage the network, along with a practical demonstration spanning multiple SDN switches. 
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  3. To interconnect research facilities across wide geographic areas, network operators deploy science networks, also referred to as Research and Education (R&E) networks. These networks allow experimenters to establish dedicated network connections between research facilities for transferring large amounts of data. Recently, R&E networks have started using Software-Defined Networking (SDN) and Software Defined Exchanges (SDX) for deploying these connections. AtlanticWave/SDX is a response to the growing demand to support end-to-end network services spanning multiple SDN domains. However, requesting these services is a challenging task for domain-expert scientists, because the interfaces of the R&E networks have been developed by network operators for network operators. In this paper, we propose interfaces that allow domain expert scientists to reserve resources of the scientific network using abstractions that focus on their data transfer needs for scientific workflow management. Recent trends in the networking field pursue better interfaces for requesting network services (e.g., intent-based networking). Although intents are sufficient for the needs of network operations, they are not abstract enough in most cases to be used by domain-expert scientists. This is an issue we are addressing in the AtlanticWave/SDX design: network operators and domain-expert scientists will have their own interfaces focusing on their specific needs. 
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  4. Poster Abstract: To interconnect research facilities across wide geographic areas, network operators deploy science networks, also referred to as Research and Education (R&E) networks. These networks allow experimenters to establish dedicated network connections between research facilities for transferring large amounts of data. Recently, R&E networks have started using Software-Defined Networking (SDN) and Software Defined Exchanges (SDX) for deploying these connections. AtlanticWave/SDX is a response to the growing demand to support end-to-end network services spanning multiple SDN domains. However, requesting these services is a challenging task for domain-expert scientists, because the interfaces of the R&E networks have been developed by network operators for network operators. In this paper, we propose interfaces that allow domain expert scientists to reserve resources of the scientific network using abstractions that focus on their data transfer needs for scientific workflow management. Recent trends in the networking field pursue better interfaces for requesting network services (e.g., intent-based networking). Although intents are sufficient for the needs of network operations, they are not abstract enough in most cases to be used by domain-expert scientists. This is an issue we are addressing in the AtlanticWave/SDX design: network operators and domain expert scientists will have their own interfaces focusing on their specific needs. 
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