Article
Chemistry, Analytical
Alejandro Rivera-Lavado, Alejandro Garcia-Lamperez, Maria-Estrella Jara-Galan, Emilio Gallo-Valverde, Paula Sanz, Daniel Segovia-Vargas
Summary: This paper proposes a low-cost passive sensor for real-time permittivity characterization of hydrocarbon fluids. The sensor's characterization is performed through both full-wave simulation and measurements, demonstrating its effectiveness in discriminating different types of crude and estimating their properties.
Article
Engineering, Chemical
Qian Chen, Zhuo Long, Naoki Shinohara, Changjun Liu
Summary: This paper presents a novel dual-band substrate integrated waveguide (SIW) sensor that can measure the complex permittivities of liquids or solid powders simultaneously. By using S-parameter measurements and applying an artificial neural network for reconstruction, the permittivities of the tested materials can be accurately and efficiently obtained.
Article
Chemistry, Analytical
Mohammad Alibakhshikenari, Bal S. Virdee, Taha A. Elwi, Innocent D. Lubangakene, Renu K. R. Jayanthi, Amer Abbood Al-Behadili, Zaid A. Abdul Hassain, Syed Mansoor Ali, Giovanni Pau, Patrizia Livreri, Sonia Aissa
Summary: This paper presents a non-invasive measurement technique to determine the permittivity of materials based on a modified metamaterial unit-cell sensor. By tightly coupling opposite sides of the sensor, two distinct resonant modes are excited, and perturbation of the fundamental mode is used to determine the permittivity. The sensitivity of the sensor is enhanced four-fold by constructing a tri-composite split-ring resonator.
Article
Engineering, Electrical & Electronic
Yatish Beria, Gouree Shankar Das, Akash Buragohain, Bijay Bikash Chamuah
Summary: This study investigates the use of a low-cost DS-CSRR sensor for accurately measuring the complex permittivity of liquid samples. The sensor operates at 2.4 GHz and exhibits high sensitivity and accuracy in measuring the permittivity of various liquids. It requires only a small volume of sample and is capable of detecting unknown samples and differentiating samples with small differences in permittivity.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Engineering, Electrical & Electronic
Akash Buragohain, Gouree Shankar Das, Yatish Beria, Ahmed Jamal Abdullah Al-Gburi, Partha Protim Kalita, Trishna Doloi
Summary: This paper presents a highly sensitive differential Hexagonal Split Ring Resonator (HSRR) sensor operating at 5.3 GHz for characterizing the permittivity of organic liquids. The sensor design is based on a hexagonal shape, which allows for better field concentration and power transfer. The sensor is capable of accurately determining the complex permittivity of unknown liquid samples with high sensitivity and immunity to environmental fluctuations.
SENSORS AND ACTUATORS A-PHYSICAL
(2023)
Article
Engineering, Electrical & Electronic
Rajeev Kumar, Surinder Singh
Summary: This article proposes a microstrip line T stub resonator as a sensor for dielectric characterization of liquid material for the development of artificial tissue-mimicking phantom. The proposed sensor is highly sensitive to a broad range of permittivity and miniaturized using Hilbert curve geometry.
IEEE SENSORS JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Athira Raveendran, Sujith Raman
Summary: This paper introduces two planar resonant sensors for measuring permittivity and identifying adulteration in vegetable oils, designed to operate in the 2.4 GHz ISM band. The sensors are capable of measuring both solid and liquid samples, with the prototypes fabricated on a 1.6 mm FR4 epoxy substrate. The experimental validation demonstrates that these sensors are capable of real time quality monitoring and permittivity measurement for both solid and liquid materials.
IEEE SENSORS JOURNAL
(2021)
Article
Chemistry, Analytical
Khuzairi Masrakin, Siti Zuraidah Ibrahim, Hasliza A. Rahim, Saidatul Norlyana Azemi, Ping Jack Soh, Sugchai Tantiviwat
Summary: This paper analyzes a microwave resonator sensor based on a square split-ring resonator operating at 5.122 GHz for permittivity characterization of a material under test (MUT). A single-ring square resonator edge (S-SRR) is coupled with several double-split square ring resonators to form the structure (D-SRR). The function of the S-SRR is to generate a resonant at the center frequency, whereas D-SRRs function as sensors, with their resonant frequency being very sensitive to changes in the MUT's permittivity.
Review
Engineering, Electrical & Electronic
Aluisio do Nascimento Wrasse, Eduardo Nunes dos Santos, Marco Jose da Silva, Hao Wu, Chao Tan
Summary: This article reviews the different capacitive sensors applied to multiphase flow measurement and imaging. It presents and discusses the operating principles, sensor geometries, and capacitive measuring circuits, along with the advantages and disadvantages focusing on flow applications and possible flow parameters yielded from sensors. Some new trends in capacitive flow sensors are also presented.
IEEE SENSORS JOURNAL
(2022)
Article
Chemistry, Analytical
S. Aiswarya, Sreedevi K. Menon, Massimo Donelli, L. Meenu
Summary: This work presents a compact dielectric sensor for detecting adulteration in solid and liquid samples using planar resonators. Six types of filter prototypes operating at 2.4 GHz were designed, optimized, numerically assessed, fabricated, and experimentally validated. The sensors showed better sensitivity, depending on the dielectric property of the sample, with a reduction in size compared to standard sensors.
Article
Physics, Applied
Chao Du, Di Zhou, Lin-Ping Feng, Tan-Tan Zhao, He-Tuo Chen, Hai-Wen Liu, Moustafa A. Darwish, Song Xia, Zhuo Xu
Summary: This paper proposes a notch structure of H-shaped dielectric patch antenna (HDPA) with wideband low-profile properties but without additional components. By integrating the H-shaped notch in the dielectric patch, the higher-order TM121 mode is made close to the dominant TM101 mode, greatly expanding the antenna's bandwidth. The accuracy of the proposed HDPA element model is evaluated using a commercial full-wave simulator.
APPLIED PHYSICS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Andrea Alimenti, Erika Pittella, Kostiantyn Torokhtii, Nicola Pompeo, Emanuele Piuzzi, Enrico Silva
Summary: A new configuration of dielectric-loaded resonator is introduced for the measurement of substrates' complex permittivity in microwave circuits, even in the presence of back metal plates. 3-D printing is utilized to create samples with different densities, allowing for the artificial manipulation of effective permittivity. The performance of the designed resonator is validated experimentally and its versatility is demonstrated in the characterization of FR4-fiberglass and Kapton polyimide samples.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Engineering, Electrical & Electronic
Meraj Ahmad, Shahid Malik, Harsh Patel, Maryam Shojaei Baghini
Summary: The paper presents a novel approach for the design of a portable, low-voltage low-power resistive sensor measurement system with high sensitivity. The proposed system utilizes a half-bridge based circuit for auto-calibrated resistive sensor interface, and reduces power consumption using square-wave excitation and demodulation. The system has the ability to measure Delta R/R-s for a wide range of baseline resistance with high resolution and programmable sensitivity. The results show that the developed system performs well in measuring minimum Delta R/R-s for different base resistors. The system is significant for low-voltage low-power sensor nodes and flexible hybrid electronics for wearable applications.
IEEE SENSORS JOURNAL
(2022)
Article
Materials Science, Multidisciplinary
Qingmin Wang, Yang Liu, Mohan Zhang, Xia Bai, Zhiwei Guo
Summary: A dielectric resonator-based sensor demonstrates high sensitivity in temperature measurement, with a simple structure conducive to sensor integration. The resonator produces strong localized electromagnetic field at resonance, allowing for accurate temperature measurement.
RESULTS IN PHYSICS
(2021)
Article
Engineering, Electrical & Electronic
Tuan-Khanh Nguyen, Chao-Hsiung Tseng
Summary: A new RF liquid permittivity measurement system is proposed, which utilizes a filter-based microfluidic sensor to integrate with an RF source, power divider, and gain/phase detector (GPD). The filter-based sensor provides a stronger electric-field concentration in the sensing area and improves sensitivity. The proposed system achieves maximum errors of -4.34% and 13.24% for e ' r and e'' r when compared with a commercial dielectric probe kit, while errors of 8.28% and 14% are achieved for e ' r and e'' r using the proposed system. The flexibility of the proposed system makes it suitable for various microfluidic sensing scenarios.
IEEE SENSORS JOURNAL
(2023)
Article
Automation & Control Systems
Michele Albano, Luis Lino Ferreira, Giovanni Di Orio, Pedro Malo, Godfried Webers, Erkki Jantunen, Iosu Gabilondo, Mikel Viguera, Gregor Papa
Article
Computer Science, Artificial Intelligence
Monika Simjanoska, Stefan Kochev, Jovan Tanevski, Ana Madevska Bogdanova, Gregor Papa, Tome Eftimov
INFORMATION FUSION
(2020)
Article
Computer Science, Information Systems
Gregor Papa, Spela Poklukar, Attila Franko, Alberto Sillitti, Ales Kancilija, Marjan Sterk, Csaba Hegedus, Istvan Moldovan, Pal Varga, Mario Riccardi, Salvatore Esposito
Article
Automation & Control Systems
Tadej Krivec, Gregor Papa, Jus Kocijan
Summary: This paper presents a method that combines variational GP approximations with a nonlinear autoregressive model to form VGP-NARX models, which show superior performance in simulating chaotic time series. The advantages of general-purpose computing on graphics processing units for Monte Carlo simulation on large validation data sets are also discussed.
Article
Chemistry, Analytical
Tamara Jakovljevic, Milica M. Jankovic, Andrej M. Savic, Ivan Soldatovic, Petar Todorovic, Tadeja Jere Jakulin, Gregor Papa, Vanja Kovic
Summary: This study examined the impact of different colors on the reading process of school-age children and found that there were differences in reading duration, EEG power bands, and eye-tracking measures among children of different ages. The study also indicated that 12 background and overlay colors influenced heart rate variability.
Article
Engineering, Multidisciplinary
Gasper Petelin, Margarita Antoniou, Gregor Papa
Summary: This paper addresses the ground station scheduling problem using six different evolutionary multi-objective algorithms and compares them with a weighted-sum approach. The results show that all multi-objective algorithms perform well and provide more alternative solutions compared to the weighted-sum method.
OPTIMIZATION AND ENGINEERING
(2023)
Article
Neurosciences
Tamara Jakovljevic, Milica M. Jankovic, Andrej M. Savic, Ivan Soldatovic, Gordana Colic, Tadeja Jere Jakulin, Gregor Papa, Vanja Kovic
Summary: Reading is essential for individual maturation, with 5-10% of school-age children affected by dyslexia. Coloured overlays and backgrounds can improve reading, especially for children with dyslexia. Different colours have varying effects on children with and without dyslexia during reading tasks.
Article
Operations Research & Management Science
Rok Hribar, Timotej Hrga, Gregor Papa, Gasper Petelin, Janez Povh, Natasa Przulj, Vida Vukasinovic
Summary: This paper considers the symmetric multi-type non-negative matrix tri-factorization problem and develops four methods to solve it using fixed point method, block-coordinate descent, gradient method, and adaptive moment estimation method. These methods are tested on synthetic and real-life similarity data sets, with ADAM showing the best performance in mean square error in most cases. If computation time is limited, FPM performs the best due to its faster convergence at the beginning.
JOURNAL OF GLOBAL OPTIMIZATION
(2022)
Article
Multidisciplinary Sciences
Tamara Jakovljevic, Milica M. Jankovic, Andrej M. Savic, Ivan Soldatovic, Ivan Macuzic, Tadeja Jere Jakulin, Gregor Papa, Vanja Kovic
Summary: This study aimed to understand gender differences in primary school students through evaluating Heart Rate Variability, Electroencephalography, Electrodermal Activities, and eye movement during reading tasks. The findings showed that boys had shorter reading duration on colored backgrounds and girls had higher HRV measurements, especially with yellow, red, and orange overlay colors.
Article
Mathematics
Margarita Antoniou, Gregor Papa
Summary: The proposed method in this work utilizes a differential evolution with an estimation of distribution algorithm to optimize worst-case scenario problems, reducing computational costs and improving efficiency.
Article
Computer Science, Artificial Intelligence
Gopal Raut, Anton Biasizzo, Narendra Dhakad, Neha Gupta, Gregor Papa, Santosh Kumar Vishvakarma
Summary: This paper proposes an improved DNN architecture that uses multiplexing to reuse hardware-costly activation functions and optimizes the memory bandwidth requirement. By extracting high-throughput and resource-efficient memory elements and tuning the order expansion, the test accuracy is improved. Experimental results show that the proposed architecture has advantages in reducing hardware resources and power consumption compared to other state-of-the-art implementations.
Article
Green & Sustainable Science & Technology
Gregor Papa, Marina Santo Zarnik, Vida Vukasinovic
Summary: The electrification of public transport in cities is expanding, and there is a great potential for fully electric buses (EBs) due to their high energy efficiency. This article provides an overview of the current state of electric-bus-related technologies and investigates the impact of route topography and climate on battery demands. There is a lack of challenging benchmark routes in Europe to test new technologies for seamless driving in difficult conditions. Although many cities have set up trial EB routes for testing under various driving conditions, there is still a need for benchmark routes in challenging environments to evaluate urban-transport electrification.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2022)
Proceedings Paper
Computer Science, Artificial Intelligence
Margarita Antoniou, Gregor Papa
Summary: When applying optimization in real-world applications, considering uncertainty is crucial for obtaining valuable optimal solutions. Min-max optimization is a way to find robust solutions that remain feasible and of good quality under worst-case scenarios. This study investigates a parallel model for differential evolution using SciPy, which can effectively solve general unconstrained min-max problems.
BIOINSPIRED OPTIMIZATION METHODS AND THEIR APPLICATIONS
(2022)
Article
Computer Science, Information Systems
Anton Biasizzo, Barbara Korousic Seljak, Eva Valencic, Marko Pavlin, Marina Santo Zarnik, Bojan Blazica, Damian O'Kelly, Gregor Papa
Summary: This study introduces an open-source solution for accurately estimating portion sizes with a pocket-sized kitchen scale and a demo mobile application. By monitoring food intake in real time, this solution has the potential to advance nutrition research and personalized nutrition tracking.