Search results for "Programming Language"
showing 10 items of 624 documents
No Reservations Required: Achieving Fairness between Wi-Fi and NR-U with Self-Deferral Only
2021
Wireless technologies coexisting in unlicensed bands should receive a fair share of the available channel resources, even when they use different access methods. We consider the problem of coexistence between Wi-Fi and New Radio Unlicensed (NR-U) nodes, which employ, respectively, a random and scheduled access scheme. The latter typically resorts to reservation signals (RSs), which allow keeping the control of the channel until the start of the next synchronized slot. This mechanism, although effective for increasing the channel access opportunities of scheduled-based nodes, is also a waste of channel resources. We investigate alternative solutions, based on self-deferral only. We built ana…
A Cognitive-based scheme for user reliability and expertise assessment in Q&A social networks
2011
Q&A social media has gained a great deal of attention during recent years. People rely on these sites to obtain information due to the number of advantages they offer as compared to conventional sources of knowledge (e.g., asynchronous and convenient access). However, for the same question one may find highly contradictory answers, causing ambiguity with respect to the correct information. This can be attributed to the presence of unreliable and/or non-expert users. In this work, we propose a novel approach for estimating the reliability and expertise of a user based on human cognitive traits. Every user can individually estimate these values based on local pairwise interactions. We examine…
An Efficient Multi-Show Unlinkable Attribute Based Credential Scheme for a Collaborative E-Health Environment
2017
Modern electronic healthcare (e-health) systems constitute collaborative environments in which patients' private health data are shared across multiple domains. In such environments, patients' privacy can be violated through the linkability of different user access sessions over patient health data. Therefore, enforcing anonymous as well as multi-session unlinkable access for the users in e-health systems is of paramount importance. As a way of achieving this requirement, more emphasis has been given to anonymous attribute credentials, which allows a user to anonymously prove the ownership of a set of attributes to a verifier and thereby gain access to protected resources. Among the existin…
Approximation-based adaptive tracking control of stochastic nonlinear systems with a general form
2014
In this paper, an approximation-based adaptive tracking control scheme is proposed for a class of stochastic nonlinear systems with a more general structure. Fuzzy logical systems are used to approximate unknown nonlinearities in the controller design procedure and the backstepping technique is utilized to construct a state-feedback adaptive controller. The proposed controller can guarantee that all the signals in the closed-loop system are fourth-moment semi-globally uniformly ultimately bounded and the tracking error eventually converges to a small neighborhood around the origin. Simulation results are used to show the effectiveness of the proposed control scheme.
Sharing Drawings with Smartphones in the Classroom – Art-Based Education in Social Sciences
2020
This article identifies the factors that indicate the opportunity of reviewing the methods in teaching economics in order to overcome the traditional teaching-learning scheme that overvalues rote learning and find formulas that facilitate the development of analytical skills. On the other hand, this work points out the importance of developing creative competences. One way to do this is to introduce artistic practices in the classroom, even in non-artistic subjects. In this work an experience of education based on the arts is presented. Thanks to smartphone cameras, students can share and project drawings in the classroom immediately to facilitate group learning. The proposal is to represen…
Elliptic Curve-Based Secure Multidimensional Aggregation for Smart Grid Communications
2017
In smart grid, data aggregation is considered as an essential paradigm in assessing information about current energy usage. To achieve the privacy-preserving goal, several homomorphic-based solutions have been proposed. However, these solutions either consider one-dimensional information or use costly pairing computation in order to ensure source authentication. In fact, smart grid data are likely to be multidimensional (e.g., time, purpose, and so on) for more accurate control. In addition, the aggregation node in smart grid needs to verify data that come from several smart meters in a residential area; hence, the verification must be cost-efficient. In this paper, we propose a scheme that…
Multi-cloud privacy preserving schemes for linear data mining
2015
This paper presents an approach to privacy-preserving data mining that relies upon a relatively simple secret sharing scheme. Its main feature is that users, sensitive data owners, are engaged in the secret sharing operations that protect their privacy. They are grouped in independent clouds connected to a central unit, the data miner, that only manages the aggregated data of each cloud, therefore avoiding the disclosure of information belonging to single nodes. We propose two privacy preserving schemes, with different privacy levels and communication costs. When designing them, we assume that some users' data might become inaccessible during the operation of the privacy preserving protocol…
A Study on scale factor in distributed differential evolution.
2011
This paper proposes the employment of multiple scale factor values within distributed differential evolution structures. Four different scale factor schemes are proposed, tested, compared and analyzed. Two schemes simply employ multiple scale factor values and two also include an update logic during the evolution. The four schemes have been integrated for comparison within three recently proposed distributed differential evolution structures and tested on several various test problems. Numerical results show that, on average, the employment of multiple scale factors is beneficial since in most cases it leads to significant improvements in performance with respect to standard distributed alg…
Quantum Probes for the Characterization of Nonlinear Media
2021
Active optical media leading to interaction Hamiltonians of the form H=λ˜(a+a†)ζ represent a crucial resource for quantum optical technology. In this paper, we address the characterization of those nonlinear media using quantum probes, as opposed to semiclassical ones. In particular, we investigate how squeezed probes may improve individual and joint estimation of the nonlinear coupling λ˜ and of the nonlinearity order ζ. Upon using tools from quantum estimation, we show that: (i) the two parameters are compatible, i.e., the may be jointly estimated without additional quantum noise
Multi-Connectivity Management for 5G V2X Communication
2019
With the advent of automated driving functions the need for cooperation among vehicles becomes increasingly necessary. The availability of high quality connectivity is an important factor for successful and uninterrupted cooperative and autonomous services. Flexible selection of available connectivity options, increases the probabilities to achieve and maintain the required Quality of Service (QoS). Future vehicles will support multiple 5G communication interfaces e.g., cellular (Uu), sidelink (PC5). A 5G RAN-based solution is proposed in this paper to dynamically select and change the communication interface that is suitable for a V2X service, considering radio and road conditions. The com…