2,358 research outputs found

    Subspace code constructions

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    We improve on the lower bound of the maximum number of planes of PG(8,q){\rm PG}(8,q) mutually intersecting in at most one point leading to the following lower bound: Aq(9,4;3)≥q12+2q8+2q7+q6+q5+q4+1{\cal A}_q(9, 4; 3) \ge q^{12}+2q^8+2q^7+q^6+q^5+q^4+1 for constant dimension subspace codes. We also construct two new non-equivalent (6,(q3−1)(q2+q+1),4;3)q(6, (q^3-1)(q^2+q+1), 4; 3)_q constant dimension subspace orbit-codes

    Combining subspace codes

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    In the context of constant--dimension subspace codes, an important problem is to determine the largest possible size Aq(n,d;k)A_q(n, d; k) of codes whose codewords are kk-subspaces of Fqn\mathbb{F}_q^n with minimum subspace distance dd. Here in order to obtain improved constructions, we investigate several approaches to combine subspace codes. This allow us to present improvements on the lower bounds for constant--dimension subspace codes for many parameters, including Aq(10,4;5)A_q(10, 4; 5), Aq(12,4;4)A_q(12, 4; 4), Aq(12,6,6)A_q(12, 6, 6) and Aq(16,4;4)A_q(16, 4; 4).Comment: 17 pages; construction for A_(10,4;5) was flawe

    The eIDAS Regulation: A Survey of Technological Trends for European Electronic Identity Schemes

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    The eIDAS regulation aims to provide an interoperable European framework to enable EU citizens to authenticate and communicate with services of other Member States by using their national electronic identity. While a number of high-level requirements (e.g., related to privacy and security) are established to make interoperability among Member States possible, the eIDAS regulation does not explicitly specify the technologies that can be adopted during the development phase to meet the requirements as mentioned earlier. To the best of our knowledge, there is no work available in the literature investigating the technological trends within the notified eIDAS electronic identity schemes used by Member States. To fill this gap, this paper analyzes how the different technological trends of notified schemes satisfy the requirements of the eIDAS regulation. To do this, we define a set of research questions that allow us to investigate the correlations between different design dimensions such as security, privacy, and usability. Based on these findings, we provide a set of lessons learned that would be valuable to the security community, as they can provide useful insights on how to more efficiently protect interoperable national digital identities. Furthermore, we provide a brief overview regarding the new eIDAS regulation (eIDAS 2.0) that aims to provide a more privacy-preserving electronic identity solution by moving from a centralized approach to a decentralized one

    Intelligent Diagnostics for Aircraft Hydraulic Equipment

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    In aviation industry, unscheduled maintenance costs may vary in a large range depending on several factors, such as specific aircraft system, operational environment, aircraft usage and maintenance policy. These costs will become more noteworthy in the next decade, due to the positive growing of worldwide fleet and the introduction of more technologically advanced aircraft. New implemented technologies will bring new challenges in the Maintenance, Repair and Overhaul (MRO) companies, both because of the rising number of new technologies and high volume of well-established devices, such as Electro-Hydraulic Servo Actuators for primary flight control. Failures in aircraft hydraulic systems deeply influence the overall failure rate and so the relative maintenance costs. For this reason, overhaul procedures for these components still represents a profitable market share for all MRO stakeholders. Innovative solutions able to facilitate maintenance operations can lead to large cost savings. This paper proposes new methodologies and features of the Intelligent Diagnostic system which is being developed in partnership with Lufthansa Technik (LHT). The implementation of this innovative procedure is built on a set of failure detection algorithms, based on Machine Learning techniques. This development requires first to bring together the results from different parallel research activities: 1. Identification of critical components from historical data; 2. Designing and testing automatic and adaptable procedure for first faults detection; 3. High-fidelity mathematical modeling of considered test units, for deeper physics analysis of possible failures; 4. Implementation of Machine Learning reasoner, able to process experimental and simulated data
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