108 research outputs found

    A Reference System Architecture with Data Sovereignty for Human-Centric Data Ecosystems

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    Since the European information economy faces insufficient access to and joint utilization of data, data ecosystems increasingly emerge as economical solutions in B2B environments. Contrarily, in B2C ambits, concepts for sharing and monetizing personal data have not yet prevailed, impeding growth and innovation. Their major pitfall is European data protection law that merely ascribes human data subjects a need for data privacy while widely neglecting their economic participatory claims to data. The study reports on a design science research (DSR) approach addressing this gap and proposes an abstract reference system architecture for an ecosystem centered on humans with personal data. In this DSR approach, multiple methods are embedded to iteratively build and evaluate the artifact, i.e., structured literature reviews, design recovery, prototyping, and expert interviews. Managerial contributions embody novel design knowledge about the conceptual development of human-centric B2C data ecosystems, considering their legal, ethical, economic, and technical constraints

    Business models and information systems for sustainable development

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    Businesses are expected to explore market opportunities in the area of sustainable development, thus contributing to finding solutions aiming at sustainable quality of life. This will require adaptation and innovation of business models and information systems, with challenges of particular interest to the business modeling and software design community. This paper briefly discusses two relevant topics in this respect, namely (i) goal and value modeling, and (ii) model-driven development. We mention existing work that can be taken as a starting point for addressing sustainability issues, and we make some observations that may be taken into account when extending existing work

    Shape characteristics of the aggregates formed by amphiphilic stars in water: dissipative particle dynamics study

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    We study the effect of the molecular architecture of amphiphilic star polymers on the shape of aggregates they form in water. Both solute and solvent are considered at a coarse-grained level by means of dissipative particle dynamics simulations. Four different molecular architectures are considered: the miktoarm star, two different diblock stars and a group of linear diblock copolymers, all of the same composition and molecular weight. Aggregation is started from a closely packed bunch of NaN_{\text a} molecules immersed into water. In most cases, a single aggregate is observed as a result of equilibration, and its shape characteristics are studied depending on the aggregation number NaN_{\text a}. Four types of aggregate shape are observed: spherical, rod-like and disc-like micelle and a spherical vesicle. We estimate "phase boundaries" between these shapes depending on the molecular architecture. Sharp transitions between aspherical micelle and a vesicle are found in most cases. The pretransition region shows large amplitude oscillations of the shape characteristics with the oscillation frequency strongly dependent on the molecular architecture.Comment: 10 pages, 7 figure

    Cooperative and non-cooperative sense-and-avoid in the CNS+A context: a unified methodology

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    A unified approach to cooperative and noncooperative Sense-and-Avoid (SAA) is presented that addresses the technical and regulatory challenges of Unmanned Aircraft Systems (UAS) integration into nonsegregated airspace. In this paper, state-of-the-art sensor/system technologies for cooperative and noncooperative SAA are reviewed and a reference system architecture is presented. Automated selection of sensors/systems including passive and active Forward Looking Sensors (FLS), Traffic Collision Avoidance System (TCAS) and Automatic Dependent Surveillance - Broadcast (ADS-B) system is performed based on Boolean Decision Logics (BDL) to support trusted autonomous operations during all flight phases. The BDL adoption allows for a dynamic reconfiguration of the SAA architecture, based on the current error estimates of navigation and tracking sensors/systems. The significance of this approach is discussed in the Communication, Navigation and Surveillance/Air Traffic Management and Avionics (CNS+A) context, with a focus on avionics and ATM certification requirements. Additionally, the mathematical models employed in the SAA Unified Method (SUM) to compute the overall uncertainty volume in the airspace surrounding an intruder/obstacle are described. In the presented methodology, navigation and tracking errors affecting the host UAS platform and intruder sensor measurements are translated to unified range and bearing uncertainty descriptors. Simulation case studies are presented to evaluate the performance of the unified approach on a representative UAS host platform and a number of intruder platforms. The results confirm the validity of the proposed unified methodology providing a pathway for certification of SAA systems that typically employ a suite of non-cooperative sensors and/or cooperative systems

    A Reusable Design for Precision Lunar Landing Systems

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    The top-level architecture to accomplish NASA's Vision for Space Exploration is to use Lunar missions and systems not just as an end in themselves, but also as testbeds for the more ambitious goals of Human Mars Exploration (HME). This approach means that Lunar missions and systems are most likely going to be targeted for (Lunar) polar missions, and also for long-duration (months) surface stays. This overacting theme creates basic top-level requirements for any next-generation lander system: 1) Long duration stays: a) Multiple landers in close proximity; b) Pinpoint landings for "surface rendezvous"; c) Autonomous landing of pre-positioned assets; and d) Autonomous Hazard Detection and Avoidance. 2) Polar and deep-crater landings (dark); 3) Common/extensible systems for Moon and Mars, crew and cargo. These requirements pose challenging technology and capability needs. Compare and contrast: 4) Apollo: a) 1 km landing accuracy; b) Lunar near-side (well imaged and direct-to-Earth com. possible); c) Lunar equatorial (landing trajectories offer best navigation support from Earth); d) Limited lighting conditions; e) Significant ground-in-the-loop operations; 5) Lunar Access: a) 10-100m landing precision; b) "Anywhere" access includes polar (potentially poor nav. support from Earth) and far side (poor gravity and imaging; no direct-to-Earth com); c) "Anytime" access includes any lighting condition (including dark); d) Full autonomous landing capability; e) Extensible design for tele-operation or operator-in-the-loop; and f) Minimal ground support to reduce operations costs. The Lunar Access program objectives, therefore, are to: a) Develop a baseline Lunar Precision Landing System (PLS) design to enable pinpoint "anywhere, anytime" landings; b) landing precision 10m-100m; c) Any LAT, LON; and d) Any lighting condition; This paper will characterize basic features of the next generation Lunar landing system, including trajectory types, sensor suite options and a reference system architecture

    Systems-of-Systems MS&A for Complex Systems, Gaming and Decision for Space Systems

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    This chapter discusses advanced modeling, simulation and analysis (MS&A) approaches for supporting complex space system, gaming and decision support system (DSS) using systems-of-systems perspective. The systems-of-systems MS&A approaches presented here also address capability-based approach for supporting US defense acquisition life cycle with a laser focus on the pre-award acquisition phase and combined game theory and wargaming for acquiring complex defense space systems. The chapter also provides an overview of existing models and tools for the design, analysis and development of the government reference system architecture solution and corresponding acquisition strategy in a complex defense systems-of-systems environment. Although, the proposed MS&A approaches presented here are focused on defense space systems, but the approaches are flexible and robust that can be extended to any civilian and commercial applications

    LIDAR obstacle warning and avoidance system for unmanned aerial vehicle sense-and-avoid

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    The demand for reliable obstacle warning and avoidance capabilities to ensure safe low-level flight operations has led to the development of various practical systems suitable for fixed and rotary wing aircraft. State-of-the-art Light Detection and Ranging (LIDAR) technology employing eye-safe laser sources, advanced electro-optics and mechanical beam-steering components delivers the highest angular resolution and accuracy performances in a wide range of operational conditions. LIDAR Obstacle Warning and Avoidance System (LOWAS) is thus becoming a mature technology with several potential applications to manned and unmanned aircraft. This paper addresses specifically its employment in Unmanned Aircraft Systems (UAS) Sense-and-Avoid (SAA). Small-to-medium size Unmanned Aerial Vehicles (UAVs) are particularly targeted since they are very frequently operated in proximity of the ground and the possibility of a collision is further aggravated by the very limited see-and-avoid capabilities of the remote pilot. After a brief description of the system architecture, mathematical models and algorithms for avoidance trajectory generation are provided. Key aspects of the Human Machine Interface and Interaction (HMI2) design for the UAS obstacle avoidance system are also addressed. Additionally, a comprehensive simulation case study of the avoidance trajectory generation algorithms is presented. It is concluded that LOWAS obstacle detection and trajectory optimisation algorithms can ensure a safe avoidance of all classes of obstacles (i.e., wire, extended and point objects) in a wide range of weather and geometric conditions, providing a pathway for possible integration of this technology into future UAS SAA architectures
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