11,743 research outputs found
Chebyshev, Legendre, Hermite and other orthonormal polynomials in D-dimensions
We propose a general method to construct symmetric tensor polynomials in the
D-dimensional Euclidean space which are orthonormal under a general weight. The
D-dimensional Hermite polynomials are a particular case of the present ones for
the case of a gaussian weight. Hence we obtain generalizations of the Legendre
and of the Chebyshev polynomials in D dimensions that reduce to the respective
well-known orthonormal polynomials in D=1 dimensions. We also obtain new
D-dimensional polynomials orthonormal under other weights, such as the
Fermi-Dirac, Bose-Einstein, Graphene equilibrium distribution functions and the
Yukawa potential. We calculate the series expansion of an arbitrary function in
terms of the new polynomials up to the fourth order and define orthonormal
multipoles. The explicit orthonormalization of the polynomials up to the fifth
order (N from 0 to 4) reveals an increasing number of orthonormalization
equations that matches exactly the number of polynomial coefficients indication
the correctness of the present procedure.Comment: 20 page
RADIS: Remote Attestation of Distributed IoT Services
Remote attestation is a security technique through which a remote trusted
party (i.e., Verifier) checks the trustworthiness of a potentially untrusted
device (i.e., Prover). In the Internet of Things (IoT) systems, the existing
remote attestation protocols propose various approaches to detect the modified
software and physical tampering attacks. However, in an interoperable IoT
system, in which IoT devices interact autonomously among themselves, an
additional problem arises: a compromised IoT service can influence the genuine
operation of other invoked service, without changing the software of the
latter. In this paper, we propose a protocol for Remote Attestation of
Distributed IoT Services (RADIS), which verifies the trustworthiness of
distributed IoT services. Instead of attesting the complete memory content of
the entire interoperable IoT devices, RADIS attests only the services involved
in performing a certain functionality. RADIS relies on a control-flow
attestation technique to detect IoT services that perform an unexpected
operation due to their interactions with a malicious remote service. Our
experiments show the effectiveness of our protocol in validating the integrity
status of a distributed IoT service.Comment: 21 pages, 10 figures, 2 table
Bright spots in the darkness of cancer: A review of starfishes-derived compounds and their anti-tumor action
The fight against cancer represents a great challenge for researchers and, for this reason, the search for new promising drugs to improve cancer treatments has become inevitable. Oceans, due to their wide diversity of marine species and environmental conditions have proven to be precious sources of potential natural drugs with active properties. As an example, in this context several studies performed on sponges, tunicates, mollusks, and soft corals have brought evidence of the interesting biological activities of the molecules derived from these species. Also, echinoderms constitute an important phylum, whose members produce a huge number of compounds with diverse biological activities. In particular, this review is the first attempt to summarize the knowledge about starfishes and their secondary metabolites that exhibited a significant anticancer effect against different human tumor cell lines. For each species of starfish, the extracted molecules, their effects, and mechanisms of action are described
Know Your Enemy: Stealth Configuration-Information Gathering in SDN
Software Defined Networking (SDN) is a network architecture that aims at
providing high flexibility through the separation of the network logic from the
forwarding functions. The industry has already widely adopted SDN and
researchers thoroughly analyzed its vulnerabilities, proposing solutions to
improve its security. However, we believe important security aspects of SDN are
still left uninvestigated. In this paper, we raise the concern of the
possibility for an attacker to obtain knowledge about an SDN network. In
particular, we introduce a novel attack, named Know Your Enemy (KYE), by means
of which an attacker can gather vital information about the configuration of
the network. This information ranges from the configuration of security tools,
such as attack detection thresholds for network scanning, to general network
policies like QoS and network virtualization. Additionally, we show that an
attacker can perform a KYE attack in a stealthy fashion, i.e., without the risk
of being detected. We underline that the vulnerability exploited by the KYE
attack is proper of SDN and is not present in legacy networks. To address the
KYE attack, we also propose an active defense countermeasure based on network
flows obfuscation, which considerably increases the complexity for a successful
attack. Our solution offers provable security guarantees that can be tailored
to the needs of the specific network under consideratio
On Koopman-von Neumann Waves II
In this paper we continue the study, started in [1], of the operatorial
formulation of classical mechanics given by Koopman and von Neumann (KvN) in
the Thirties. In particular we show that the introduction of the KvN Hilbert
space of complex and square integrable "wave functions" requires an enlargement
of the set of the observables of ordinary classical mechanics. The possible
role and the meaning of these extra observables is briefly indicated in this
work. We also analyze the similarities and differences between non selective
measurements and two-slit experiments in classical and quantum mechanics.Comment: 18+1 pages, 1 figure, misprints fixe
Metabolic syndrome and the immunological affair with the blood-brain barrier
Copyright © 2015 Mauro, De Rosa, Marelli-Berg and Solito. This is an open-access
article distributed under the terms of the
Creative Commons Attribution License (CC
BY)
. The use, distribution or reproduction in other forums is permitted, provided the
original author(s) or licensor are credited and that the original publication in this
journal is cited, in accordance with accepted academic practice. No use, distribution or
reproduction is permitted which does not comply with these terms
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