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1.
Cognit Comput ; 14(1): 62-77, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33558822

RESUMO

In recent years, SenticNet and OntoSenticNet have represented important developments in the novel interdisciplinary field of research known as sentic computing, enabling the development of a variety of Sentic applications. In this paper, we propose an extension of the OntoSenticNet ontology, named DomainSenticNet, and contribute an unsupervised methodology to support the development of domain-aware Sentic applications. We developed an unsupervised methodology that, for each concept in OntoSenticNet, mines semantically related concepts from WordNet and Probase knowledge bases and computes domain distributional information from the entire collection of Kickstarter domain-specific crowdfunding campaigns. Subsequently, we applied DomainSenticNet to a prototype tool for Kickstarter campaign authoring and success prediction, demonstrating an improvement in the interpretability of sentiment intensities. DomainSenticNet is an extension of the OntoSenticNet ontology that integrates each of the 100,000 concepts included in OntoSenticNet with a set of semantically related concepts and domain distributional information. The defined unsupervised methodology is highly replicable and can be easily adapted to build similar domain-aware resources from different domain corpora and external knowledge bases. Used in combination with OntoSenticNet, DomainSenticNet may favor the development of novel hybrid aspect-based sentiment analysis systems and support further research on sentic computing in domain-aware applications.

2.
Opt Express ; 27(8): 10644-10658, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31052919

RESUMO

We demonstrate a Distributed Acoustic Sensor (DAS) based on Ultra-Weak Fiber Bragg Gratings (UWFBGs) using a scalable homodyne demodulation in direct detection. We show that a distributed interferometric system using delay and mixing of backscattering from consecutive identical gratings can be combined with a Phase-Generated Carrier Differentiate and Cross-Multiply (PGC-DCM) demodulation algorithm to perform dynamic measurements with high SNR, employing a simple narrowband laser and a pin photodiode. The proposed homodyne demodulation technique is suitable for real-time monitoring using distributed measurements, as it does not require computationally costly phase unwrapping common in conventional schemes and is robust against detrimental harmonic distortions, while not requiring additional mechanisms to handle division-by-zero operations. The demodulation scheme is also scalable, as it involves symmetric ordinary differentiation and integration operations suitable for processing with FPGA-based or analogue systems which, thanks to readily realizable schemes for implementing fractional order calculus, are also candidates for small-scale integration. We experimentally demonstrate the effectiveness of the technique by monitoring the dynamic response of a generic 2.5 kHz vibration applied to a PZT placed at the end of a sensing fiber comprised of a 1 km array of 200 UWFBGs each with a reflectivity of ~-43 dB written at a spacing of 5 m, with an SNR of ~34.52 dB.

3.
Nutrients ; 10(11)2018 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-30400278

RESUMO

Iron deficiency represents a widespread problem for a large part of the population, especially for women, and has received increasing attention in food/supplement research. The contraindications of the iron supplements commercially available (e.g., imbalances in the levels of other essential nutrients, low bioavailability, etc.) led us to search for a possible alternative. In the present work, a rapid and easy method to synthetize a solid iron (II) citrate complex from iron filings and citric acid was developed to serve, eventually, as a food supplement or additive. In order to state its atomic composition and purity, an assortment of analytical techniques was employed (e.g., combustion analysis, thermogravimetry, X-ray diffractometry, UV/Vis spectrophotometry, etc.). Results demonstrate that the synthesized crystalline solid corresponds to the formula FeC6H6O7∙H2O and, by consequence, contains exclusively iron (II), which is an advantage with respect to existing commercial products, because iron (II) is better absorbed than iron (III) (high bioavailability of iron).


Assuntos
Ácido Cítrico/química , Ferro da Dieta/síntese química , Ferro/química , Disponibilidade Biológica , Carbono/análise , Suplementos Nutricionais , Ferro da Dieta/farmacocinética , Modelos Teóricos , Termogravimetria , Difração de Raios X
4.
Opt Lett ; 43(21): 5471-5474, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30383035

RESUMO

A packaged photonic integrated network-on-chip (NoC) based on multi-microrings with a controller and scheduler implemented in FPGA is demonstrated under dynamic packet-switched traffic. Multiple transmission scenarios have been investigated, comprising up to three interfering signals at the same wavelength. The dynamic switching exhibits a power penalty of approximately 0.5 dB at a BER of 10-9. The presence of up to three interferers induces a power penalty below 1 dB.

5.
Foods ; 7(9)2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30149529

RESUMO

Pasta with eggs added (generally termed "special pasta" for Italian legislation) is made by adding no less than 4 eggs without shells (or no less than 200 g of liquid or lyophilized egg product) per kilogram of semolina, as provided by law. In this work, to determine the final content of eggs added to dough, an analytical procedure was developed for the rapid analysis of the cholesterol content in the finished pastas. The proposed procedure was simpler, faster, and more accurate than that of official methods of analysis based on the gravimetric determination of sterols. Moreover, the determination of the quality of fat content in the special pasta (egg pasta in this case) allowed the evaluation of its origin, avoiding possible fraud resulting from the addition of foreign fat as an alternative to fat derived from eggs. In this new gas chromatographic procedure, the internal standard squalene for the quantification of cholesterol was used because a more polar GC capillary column was used (RTX 65 TG-HT) for the separation of sterols, rather than 5% phenyl methylsilicone. The ratio between cholesterol and squalene allowed for the determination of the number of eggs added, while from analysis of the same gas chromatogram, it was also possible to evaluate the composition of triglycerides in the fat contained in the pasta, allowing discrimination of foreign fats with respect to fats contained in eggs and therefore avoiding adulteration of pasta. The same analytical procedure was applied to the determination of cholesterol content in lyophilized yolk.

6.
Opt Express ; 26(2): 687-701, 2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29401951

RESUMO

We propose and experimentally demonstrate a stable homodyne phase demodulation technique in a ϕ-OTDR using a double-pulse probe and a simple direct detection receiver. The technique uses selective phase modulation of one of a pair of pulses to generate a carrier for dynamic phase changes and involves an enhanced phase demodulation scheme suitable for distributed sensing by being robust against light intensity fluctuations, independent of the modulation depth, and convenient for analogue signal processing. The capability of the technique to quantify distributed dynamic phase change due to a generic external impact is experimentally demonstrated by measuring the phase change induced by a nonlinear actuator generating a 2 kHz perturbation at a distance of 1.5 km on a standard singlemode fiber with an SNR of ~24 dB. The demodulated nonlinear response is shown to have a spectrum consistent with one obtained using an FBG sensor and a commercial reading unit.

7.
Opt Express ; 25(18): 22004-22016, 2017 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-29041490

RESUMO

A 24-port packaged multi-microring optical network-on-chip has been tested for simultaneous co- and counter-propagating transmissions at the same wavelength at 10 Gbps. In the co-propagating scenario communications up to five hops with one interfering signal have been tested, together with transmissions impaired by up to three interfering signals. In the counter-propagating scenario the device performance has been investigated exploiting the ring resonators in both shared-source and shared-destination configurations. The spectral characterization is in good agreement with the theoretical results. Bit-error-rate measurements indicate power penalties at BER=10-9 limited to (i) 0.5 dB in the co-propagating scenarios independently from the number of interfering transmissions, (ii) 0.8 dB in the counter-propagating scenario with shared-source configuration, and (iii) 2 dB in the counter-propagating scenario with shared-destination configuration.

8.
Opt Lett ; 41(3): 587-90, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26907430

RESUMO

We demonstrate a hybrid distributed acoustic and temperature sensor (DATS) using a commercial off-the-shelf (COTS) distributed feedback (DFB) laser, a single-mode optical fiber, and a common receiver block. We show that the spectral and frequency noise characteristics of the laser, combined with a suitable modulation scheme, ensure the inter-pulse incoherence and intra-pulse coherence conditions required for exploiting the fast denoising benefits of cyclic Simplex pulse coding in the hybrid measurement. The proposed technique enables simultaneous, distributed measurement of vibrations and temperature, with key industrial applications in structural health monitoring and industrial process control systems. The sensor is able to clearly identify a 500 Hz vibration at 5 km distance along a standard single-mode fiber and simultaneously measure the temperature profile along the same fiber with a temperature resolution of less than 0.5°C with 5 m spatial resolution.

9.
Opt Express ; 23(13): 17169-78, 2015 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-26191725

RESUMO

The operation of an integrated silicon-photonics multi-microring network-on-chip (NoC) is experimentally demonstrated in terms of transmission spectra and bit error rates at 10 Gb/s. The integrated NoC consists of 8 thermally tuned microrings coupled to a central ring. The switching functionalities are tested with concurrent transmissions at both the same and different wavelengths. Experimental results validate the analytical model based on the transfer matrix method. BER measurements show performance up to 10(-9) at 10 Gb/s with limited crosstalk and penalty (below 0.5 dB) induced by an interfering transmission.

10.
Opt Express ; 22(2): 2150-8, 2014 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-24515225

RESUMO

An integrated noncoherent silicon receiver for demodulation of 100-Gb/s polarization-division multiplexed differential quadrature phase-shift keying and polarization-division multiplexed differential binary phase-shift keying signals is demonstrated. The receiver consists of a 2D surface grating coupler, four Mach-Zehnder delay interferometers and four germanium balanced photodetectors.

11.
Opt Express ; 21(18): 20649-55, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-24103938

RESUMO

This paper presents a novel Indium Phosphide based photonic integrated circuit (PIC) for all-optical regeneration of both nonreturn-to-zero (NRZ) and return-to-zero (RZ) on-off-keying (OOK) signals. The PIC exploits cross gain compression in two semiconductor optical amplifiers to simultaneously obtain a wavelength-preserved and reshaped copy, and a wavelength-converted yet inverted copy of the input signal. Regeneration of 10 Gb/s signals on multiple wavelengths is demonstrated, showing a Q-factor improvement from 1.5 to 4 for NRZ-OOK signals and from 2.3 to 3.6 for RZ-OOK signals, and a BER improvement up to 1.5 decades.

12.
Opt Lett ; 37(21): 4434-6, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23114320

RESUMO

We propose and experimentally demonstrate a hybrid fiber optic sensing technique that effectively combines Raman optical time domain reflectometry and in-line time-division-multiplexing for fiber Bragg grating (FBG) dynamic interrogation. The highly integrated proposed scheme employs broadband apodized low reflectivity FBGs with a single narrowband optical source and a shared receiver block, allowing for simultaneous measurements of distributed static temperature and discrete dynamic strain, over the same sensing fiber.

13.
Opt Express ; 20(18): 19726-34, 2012 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23037025

RESUMO

A monolithic 25 Gbaud DQPSK receiver based on delay interferometers and balanced detection has been designed and fabricated on the hybrid Si/InGaAs platform. The integrated 30 µm long InGaAs p-i-n photodetectors have a responsivity of 0.64 A/W at 1550 nm and a 3dB bandwidth higher than 25 GHz. The delay interferometer shows a delay time of 39.2 ps and an extinction ratio higher than 20 dB. The demodulation of a 25 Gb/s DPSK signal by a single branch of the receiver demonstrates its correct working principle.


Assuntos
Interferometria/instrumentação , Telecomunicações/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Micro-Ondas , Integração de Sistemas
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