47 research outputs found

    The need for international planetary cartography planning and cooperation

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    Cartography is fundamental to planetary science and as such, a lack of appropriate consideration of this foundation can have and has had serious and expensive consequences to both the scientific return from planetary missions and the safety of future lander missions. In this abstract we highlight the need for, and recommend cooperative planning of, such cartographic work at the national and international level. In an effort to support the planetary exploration initiatives of the various spacefaring nations, we detail specific negative consequences of not properly accounting for cartographic constraints during mission planning and execution. We will also pose several unanswered questions that must be addressed before new exploration efforts should commence. To assure the best possible return on space exploration investments, we recommend that the following planetary cartographic issues be considered: 1. Adequate resources for mapping at all stages from mission design through calibration, operations, development of processing algorithms and software, and processing to archiving; 2. Easy access to data sets and metadata from all nations; consistent (or at least well-documented) data formats; consistent cartographic standards; 3. Cooperation and support leading to the joint analysis of data sets from many nations, in turn leading to integration in a single cartographic coordinate framework at known accuracy levels, and the ability to leverage the powerful synergistic value of multiple data sets. Possible actions that could be taken to achieve these goals will also be presented

    RiPKI: The Tragic Story of RPKI Deployment in the Web Ecosystem

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    Previous arXiv version of this paper has been published under the title "When BGP Security Meets Content Deployment: Measuring and Analysing RPKI-Protection of Websites", Proc. of Fourteenth ACM Workshop on Hot Topics in Networks (HotNets), New York:ACM, 2015Previous arXiv version of this paper has been published under the title "When BGP Security Meets Content Deployment: Measuring and Analysing RPKI-Protection of Websites", Proc. of Fourteenth ACM Workshop on Hot Topics in Networks (HotNets), New York:ACM, 2015Web content delivery is one of the most important services on the Internet. Access to websites is typically secured via TLS. However, this security model does not account for prefix hijacking on the network layer, which may lead to traffic blackholing or transparent interception. Thus, to achieve comprehensive security and service availability, additional protective mechanisms are necessary such as the RPKI, a recently deployed Resource Public Key Infrastructure to prevent hijacking of traffic by networks. This paper argues two positions. First, that modern web hosting practices make route protection challenging due to the propensity to spread servers across many different networks, often with unpredictable client redirection strategies, and, second, that we need a better understanding why protection mechanisms are not deployed. To initiate this, we empirically explore the relationship between web hosting infrastructure and RPKI deployment. Perversely, we find that less popular websites are more likely to be secured than the prominent sites. Worryingly, we find many large-scale CDNs do not support RPKI, thus making their customers vulnerable. This leads us to explore business reasons why operators are hesitant to deploy RPKI, which may help to guide future research on improving Internet security

    Surface softening in metal-ceramic sliding contacts: An experimental and numerical investigation

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    This study investigates the tribolayer properties at the interface of ceramic/metal (i.e., WC/W) sliding contacts using various experimental approaches and classical atomistic simulations. Experimentally, nanoindentation and micropillar compression tests, as well as adhesion mapping by means of atomic force microscopy, are used to evaluate the strength of tungsten?carbon tribolayers. To capture the influence of environmental conditions, a detailed chemical and structural analysis is performed on the worn surfaces by means of XPS mapping and depth profiling along with transmission electron microscopy of the debris particles. Experimentally, the results indicate a decrease in hardness and modulus of the worn surface compared to the unworn one. Atomistic simulations of nanoindentation on deformed and undeformed specimens are used to probe the strength of the WC tribolayer and despite the fact that the simulations do not include oxygen, the simulations correlate well with the experiments on deformed and undeformed surfaces, where the difference in behavior is attributed to the bonding and structural differences of amorphous and crystalline W-C. Adhesion mapping indicates a decrease in surface adhesion, which based on chemical analysis is attributed to surface passivation

    Planetary Cartography and Mapping: Where we are today, and where we are heading for?

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    Planetary Cartography does not only provides the basis to support planning (e.g., landing site selection, orbital observations, traverse planning) and to facilitate mission conduct during the lifetime of a mission (e.g., observation tracking and hazard avoidance). It also provides the means to create science products after successful termination of a planetary mission by distilling data into maps. After a missions lifetime, data and higher level products like mosaics and digital terrain models (DTMs) are stored in archives, and eventually into maps and higher level data products, to form a basis for research and for new scientific and engineering studies. The complexity of such tasks increases with every new dataset that has been put on this stack of information, and in the same way as the complexity of autonomous probes increases, also tools that support these challenges require new levels of sophistication. In planetary science, cartography and mapping have a history dating back to the roots of telescopic space exploration and are now facing new technological and organizational challenges with the rise of new missions, new global initiatives, organizations and opening research markets. The focus of this contribution is to summarize recent activities in Planetary Cartography, highlighting current issues the community is facing to derive the future opportunities in this field. By this we would like to invite cartographers/researchers to join this community and to start thinking about how we can jointly solve some of these challenges

    Cartography Support and Assessment of Candidate Landing Sites for the "Luna-Glob" Mission

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    For cartography support of future landing mission LUNA-GLOB was development a geodatabase using data obtained by LRO. For characterization of the surface we created some examples of maps: slope, roughness, and hill-shaded relief in various scales

    Forum: Making Peace with Un-Certainty: Reflections on the Role of Digital Technology in Peace Processes beyond the Data Hype

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    Recent years have seen the acceleration of data- and evidence-based approaches in support of peace processes, creating a renewed confidence that conflicts can be predicted, known, and resolved, based on objective information about the world. However, new technologies employed by conflict parties, stakeholders, and those who aim to make or build peace have also made peace processes less ascertainable, intelligible, and predictable. Technology can thus create both more certainty and uncertainty in (and about) peace processes. This forum article presents a first collaborative attempt to explore how the use of technology by conflict parties and peacebuilding actors influences these dynamics. We examine various fields of engagement, ranging from conflict prevention to peace mediation, peacekeeping, and longer-term peacebuilding. Our discussion engages with a variety of related activities, including predictive analysis and foresight, conflict analysis, cease-fire monitoring, early warning and early action, and problem-solving and trust-building dialogues. We suggest approaching un-certainty as a spectrum between uncertainty and certainty that can be studied across epistemic, ontological, and normative dimensions, thus inviting further academic research and policy reflection. The article is coauthored by scholars and current or former practitioners and underlines the necessity, benefits, and feasibility of research–practice exchanges on this topic
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