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A Hierarchical Optimization Strategy for Energy Scheduling and Volt/var Control in Autonomous Clusters of Microgrids
No full textImproving ns-3 Emulation Performance for Fast Prototyping of Routing and SDN Protocols: Moving Data Plane Operations to Outside of ns-3
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A Self-Referencing Intensity-Based Fabry–Perot Cavity for Curvature Measurement
Get PDFIn this article, a self-referencing intensity-based fiber optic sensor relying on the principle of Fabry–Perot
interference is proposed and demonstrated to measure curvature. The sensor is manufactured producing an air bubble cavity between two sections of multimode fiber. By detecting optical power variations at specific wavelengths, it was possible to measure curvature, enabling this sensor as a self-referencing system. For this setup, the achieved curvature sensitivity was 0.561 ± 0.014 dB/m−1, with a correlation factor up to 0.997, within the measurement range of 0.0–0.8 m−1.
The proposed system has several features, including the self-referencing characteristic and its structure simplicity in terms of measuring procedure, making it a useful system
Resonant tunneling diode photodetectors for optical communications
Get PDFOptical modulation characteristics of resonant tunneling diode photodetectors (RTD-PD) are investigated. Intensity modulated light excites the RTD-PDs to conduct data experiments. Simple and complex data patterns are used with results showing data rates up to 80 and 200 Mbit/s, respectively. This is the first demonstration of complex modulation using resonant tunneling diodes. © 2019 The Authors. Microwave and Optical Technology Letters published by Wiley Periodicals, Inc
Rapid detection of spammers through collaborative information sharing across multiple service providers
Get PDFSpammers and telemarketers target a very large number of recipients usually dispersed across many Service Providers (SPs). Collaboration and Information sharing between SPs would increase the detection accuracy but detection effectiveness depends on the amount of information shared between SPs. Having service provider's exchange call detail records would arguably attain the best detection accuracy but would require significant network resources. Moreover, SPs are likely to feel uncomfortable in sharing their call records because call records contain user's private information as well as operational details of their networks. The challenge towards the design of collaborative Spam over Internet Telephony (SPIT) detection system is two-fold: it should attain high detection accuracy with a small false positive, and should fully protect the privacy of users and their service providers. In this paper, we propose a COllaborative Spit Detection System (COSDS)-a collaborative SPIT detection system for the Voice over IP (VoIP) network where service providers collaborate for the effective and early detection of SPIT callers without raising privacy concerns. To this extent, COSDS relies on a trusted Centralized Repository (CR) and exchange of non-sensitive reputation scores. The CR computes global reputation of users by aggregating the reputation scores provided by the respective collaborating SPs. The data exchanged to the CR is not sensitive regarding users privacy, and cannot be used to infer the relationship network of users. We evaluate the performance of our system using synthetic data that we have generated by simulating the realistic social behavior of spammers and non-spammers in a network. The results show that the COSDS approach has better detection accuracy as compared to the traditional stand-alone detection systems. For instances, in a setup where spammers are making calls to recipients of many SPs, COSDS successfully identifies spammers with the True Positive (TP) rate of around 80% and false positive (FP) rate of around 2% on a first day, which further increases to 100% TP rate and zero FP rate in three days. COSDS approach is fast, requires a small communication overhead, ensures privacy of users and collaborating SP, and requires only few iterations for the reputation convergence within the SP. © 2018 Elsevier B.V
Multiplexing optical fiber Fabry-Perot interferometers based on airmicrocavities
Get PDFIn this work we demonstrate the multiplexing capability of new optical fiber Fabry-Perot interferometers based on airmicrocavities
using a commercial FBG interrogator. Three optimized air-microcavity interferometer sensors have been
multiplexed in a single network and have been monitored using the commercial FBGs interrogator in combination with
FFT calculations. Results show a sensitivity of 2.18 π rad/mε and a crosstalk-free operation.This work was supported by the Spanish AEI TEC2016-76021-C2, FEDER Funds; and also by the ERDF – European Regional Development Fund through the Operational Programme for Competitiveness and Internationalization - COMPETE 2020 Programme and by National Funds through the Portuguese funding agency, FCT - Fundação para a Ciência e a Tecnologia within project ENDOR - Endoscope based on New Optical Fibre Technology for Raman Spectroscopy (POCI-01-0145-FEDER-029724). M. Bravo received funding from Marie Skłodowska-Curie grant agreement No 838143
Generalising KAT to Verify Weighted Computations
Get PDFKleene algebra with tests (KAT) was introduced as an algebraic structure to model and reason about classic imperative programs, i.e. sequences of discrete transitions guarded by Boolean tests. This paper introduces two generalisations of this structure able to express programs as weighted transitions and tests with outcomes in non necessarily bivalent truth spaces: graded Kleene algebra with tests (GKAT) and a variant where tests are also idempotent (I-GKAT). In this context, and in analogy to Kozen's encoding of Propositional Hoare Logic (PHL) in KAT we discuss the encoding of a graded PHL in I-GKAT and of its while-free fragment in GKAT. Moreover, to establish semantics for these structures four new algebras are defined: FSET(T), FREL(K,T) and FLANG(K,T) over complete residuated lattices K and T, and M (n, A) over a GKAT or I-GKAT A. As a final exercise, the paper discusses some program equivalence proofs in a graded context
Development and Field Demonstration of a Gamified Residential Demand Management Platform Compatible with Smart Meters and Building Automation Systems
Get PDFDemand management is becoming an indispensable part of grid operation with its potential to aid supply/demand balancing, reduce peaks, mitigate congestions and improve voltage profiles in the grid. Effective deployments require a huge number of reliable participators who are aware of the flexibilities of their devices and who continuously seek to achieve savings and earnings. In such applications, smart meters can ease consumption behavior visibility, while building automation systems can enable the remote and automated control of flexible loads. Moreover, gamification techniques can be used to motivate and direct customers, evaluate their performance, and improve their awareness and knowledge in the long term. This study focuses on the design and field demonstration of a flexible device-oriented, smart meter and building automation system (BAS) compatible with a gamified load management (LM) platform for residential customers. The system is designed, based on exploratory surveys and systematic gamification approaches, to motivate the customers to reduce their peak period consumption and overall energy consumption through competing or collaborating with others, and improving upon their past performance. This paper presents the design, development and implementation stages, together with the result analysis of an eight month field demonstration in four houses with different user types in Istanbul, Turkey
Fostering Professional Competencies in Engineering Undergraduates with EPS@ISEP
Get PDFEngineering education addresses the development of professional competencies inundergraduates. In this context, the core set of professional competencies includes critical thinkingand problem solving, effective communication, collaboration and team building, and creativityand innovation—also known as the four Cs—as well as socio-professional ethics and sustainabledevelopment—referred in this paper as the two Ss. While the four Cs were identified by theassociates of the American Management Association based on the needs of the society, professionalassociations, and businesses; this paper proposes the two S extension to ensure that future engineerscontribute to the well-being of individuals and the preservation of life on Earth. It proposes atangible framework—the 4C2S—and an application method to analyse the contributions madeby engineering capstone programmes to the development of these core competencies in futureengineering professionals. The method is applied to an engineering capstone programme—theEuropean Project Semester (EPS) offered by the Instituto Superior de Engenharia do Porto (ISEP)—anda specific project case—EPS@ISEP Pet Tracker project developed in 2013, constituting, in addition,a road map for the application of the 4C2S framework to engineering capstone programmes. Theresults show that EPS@ISEP complies with the 4C2S framework.</jats:p