17,469 research outputs found

    Prototyping Operational Autonomy for Space Traffic Management

    Get PDF
    Current state of the art in Space Traffic Management (STM) relies on a handful of providers for surveillance and collision prediction, and manual coordination between operators. Neither is scalable to support the expected 10x increase in spacecraft population in less than 10 years, nor does it support automated manuever planning. We present a software prototype of an STM architecture based on open Application Programming Interfaces (APIs), drawing on previous work by NASA to develop an architecture for low-altitude Unmanned Aerial System Traffic Management. The STM architecture is designed to provide structure to the interactions between spacecraft operators, various regulatory bodies, and service suppliers, while maintaining flexibility of these interactions and the ability for new market participants to enter easily. Autonomy is an indispensable part of the proposed architecture in enabling efficient data sharing, coordination between STM participants and safe flight operations. Examples of autonomy within STM include syncing multiple non-authoritative catalogs of resident space objects, or determining which spacecraft maneuvers when preventing impending conjunctions between multiple spacecraft. The STM prototype is based on modern micro-service architecture adhering to OpenAPI standards and deployed in industry standard Docker containers, facilitating easy communication between different participants or services. The system architecture is designed to facilitate adding and replacing services with minimal disruption. We have implemented some example participant services (e.g. a space situational awareness provider/SSA, a conjunction assessment supplier/CAS, an automated maneuver advisor/AMA) within the prototype. Different services, with creative algorithms folded into then, can fulfil similar functional roles within the STM architecture by flexibly connecting to it using pre-defined APIs and data models, thereby lowering the barrier to entry of new players in the STM marketplace. We demonstrate the STM prototype on a multiple conjunction scenario with multiple maneuverable spacecraft, where an example CAS and AMA can recommend optimal maneuvers to the spacecraft operators, based on a predefined reward function. Such tools can intelligently search the space of potential collision avoidance maneuvers with varying parameters like lead time and propellant usage, optimize a customized reward function, and be implemented as a scheduling service within the STM architecture. The case study shows an example of autonomous maneuver planning is possible using the API-based framework. As satellite populations and predicted conjunctions increase, an STM architecture can facilitate seamless information exchange related to collision prediction and mitigation among various service applications on different platforms and servers. The availability of such an STM network also opens up new research topics on satellite maneuver planning, scheduling and negotiation across disjoint entities

    Towards a Rule Interchange Language for the Web

    Get PDF
    This articles discusses rule languages that are needed for a a full deployment of the SemanticWeb. First, it motivates the need for such languages. Then, it presents ten theses addressing (1) the rule and/or logic languages needed on the Web, (2) data and data processing, (3) semantics, and (4) engineering and rendering issues. Finally, it discusses two options that might be chosen in designing a Rule Interchange Format for the Web

    Lex Informatica: The Formulation of Information Policy Rules through Technology

    Get PDF
    Historically, law and government regulation have established default rules for information policy, including constitutional rules on freedom of expression and statutory rights of ownership of information. This Article will show that for network environments and the Information Society, however, law and government regulation are not the only source of rule-making. Technological capabilities and system design choices impose rules on participants. The creation and implementation of information policy are embedded in network designs and standards as well as in system configurations. Even user preferences and technical choices create overarching, local default rules. This Article argues, in essence, that the set of rules for information flows imposed by technology and communication networks form a “Lex Informatica” that policymakers must understand, consciously recognize, and encourage

    Competition for Partners: Strategic Games in Wholesale International Roaming

    Get PDF
    High international roaming prices have puzzled and occupied analysts and regulators for quite a time. While on the retail side the problem seems to be well understood, and the high margins can be justified using Ramsey pricing logic, on the wholesale side the picture is not so clear. Recent contributions find reasons for regulation based on the existence of random traffic and on the bilateral nature of the wholesale deals, which raise the equilibrium prices even when operators can choose a preferred network. This paper intends to investigate whether or not those concerns are justified. This is done by modelling the bilateral roaming negotiations and extending the current models, assuming that home operators (the ones with a retail contract with the customer in its country of residence) can decide not only their preferred network in each visited country, but also the distribution of their outbound traffic among the visited operators. We find that when traffic steering is perfect the wholesale market is competitive, and that the lower prices are passed on to end users through competition for retail customers. The bilateral nature of international roaming wholesale deals is actually an additional source of competition on the retail market for mobile services because the roaming out traffic (the traffic of an operator's retail customers abroad) and the roaming in traffic (the traffic of foreign customers that an operator is able to attract) are directly linked. --

    Online Dispute Resolution: Stinky, Repugnant, or Drab?

    Get PDF
    corecore