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Hruška M, More-Chevalier J, Fitl P, Novotný M, Hruška P, Prokop D, Pokorný P, Kejzlar J, Gadenne V, Patrone L, Vrňata M, Lančok J. Surface Enhancement Using Black Coatings for Sensor Applications. Nanomaterials (Basel) 2022; 12:4297. [PMID: 36500920 PMCID: PMC9738287 DOI: 10.3390/nano12234297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
The resolution of a quartz crystal microbalance (QCM) is particularly crucial for gas sensor applications where low concentrations are detected. This resolution can be improved by increasing the effective surface of QCM electrodes and, thereby, enhancing their sensitivity. For this purpose, various researchers have investigated the use of micro-structured materials with promising results. Herein, we propose the use of easy-to-manufacture metal blacks that are highly structured even on a nanoscale level and thus provide more bonding sites for gas analytes. Two different black metals with thicknesses of 280 nm, black aluminum (B-Al) and black gold (B-Au), were deposited onto the sensor surface to improve the sensitivity following the Sauerbrey equation. Both layers present a high surface roughness due to their cauliflower morphology structure. A high response (i.e., resonant frequency shift) of these QCM sensors coated with a black metal layer was obtained. Two gaseous analytes, H2O vapor and EtOH vapor, at different concentrations, are tested, and a distinct improvement of sensitivity is observed for the QCM sensors coated with a black metal layer compared to the blank ones, without strong side effects on resonance frequency stability or mechanical quality factor. An approximately 10 times higher sensitivity to EtOH gas is reported for the QCM coated with a black gold layer compared to the blank QCM sensor.
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Affiliation(s)
- Martin Hruška
- Department of Physics and Measurements, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
| | - Joris More-Chevalier
- Department of Physics and Measurements, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
- Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague, Czech Republic
| | - Přemysl Fitl
- Department of Physics and Measurements, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
- Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague, Czech Republic
| | - Michal Novotný
- Department of Physics and Measurements, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
- Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague, Czech Republic
| | - Petr Hruška
- Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague, Czech Republic
- Faculty of Mathematics and Physics, Charles University, V Holesovickach 2, 180 00 Prague, Czech Republic
| | - Dejan Prokop
- Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague, Czech Republic
- Faculty of Mathematics and Physics, Charles University, V Holesovickach 2, 180 00 Prague, Czech Republic
| | - Petr Pokorný
- Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague, Czech Republic
| | - Jan Kejzlar
- Department of Physics and Measurements, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
- Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague, Czech Republic
| | - Virginie Gadenne
- ISEN Yncréa Méditerranée, Aix Marseille Univ, Université de Toulon, CNRS, IM2NP, 83000 Toulon, France
| | - Lionel Patrone
- ISEN Yncréa Méditerranée, Aix Marseille Univ, Université de Toulon, CNRS, IM2NP, 83000 Toulon, France
| | - Martin Vrňata
- Department of Physics and Measurements, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
| | - Jan Lančok
- Department of Physics and Measurements, University of Chemistry and Technology Prague, Technicka 5, 166 28 Prague, Czech Republic
- Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague, Czech Republic
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2
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Chmielinski MJ, Cohen MA, Yost MG, Simpson CD. Wearable Spectroradiometer for Dosimetry. Sensors (Basel) 2022; 22:8829. [PMID: 36433426 PMCID: PMC9697616 DOI: 10.3390/s22228829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/08/2022] [Accepted: 11/09/2022] [Indexed: 06/16/2023]
Abstract
Available wearable dosimeters suffer from spectral mismatch during the measurement of broadband UV and visible radiation in environments that receive radiation from multiple sources emitting differing spectra. We observed this type of multi-spectra environment in all five Washington State cannabis farms visited during a field study investigating worker exposure to ultraviolet radiation in 2018. Spectroradiometers do not suffer from spectral mismatch in these environments, however, an extensive literature review conducted at the time of writing did not identify any spectroradiometers that were directly deployable as wearable dosimetry devices. To close this research gap, we developed a microcontroller system and platform that allows for researchers to mount and deploy the Ocean Insight Flame-S Spectroradiometer as a wearable device for measurement of UV and visible wavelengths (300 to 700 nm). The platform validation consisted of comparing measurements taken under platform control with measurements taken with the spectrometer controlled by a personal computer running the software provided by the spectroradiometer manufacturer. Three Mann-Whitney U-Tests (two-tailed, 95% CI), one for each intensity condition, compared the central tendency between the total spectral power (TSP), the integral of a spectrum measurement, measured under both control schemas. An additional analysis of per pixel agreement and overall platform stability was performed. The three Mann-Whitney tests returned no significant difference between the set of TSPs for each filter condition. These results suggest that the spectroradiometer takes measurements of equivalent accuracy under both control schemas, and can be deployed as a wearable device for the measurement of wavelength resolved UV and visible radiation.
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Affiliation(s)
| | | | | | - Christopher D. Simpson
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA 98105, USA
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3
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Zhang T, Shen Y, Kiya R, Anggraini D, Tang T, Uno H, Okano K, Tanaka Y, Hosokawa Y, Li M, Yalikun Y. Focusing of Particles in a Microchannel with Laser Engraved Groove Arrays. Biosensors (Basel) 2021; 11:263. [PMID: 34436065 DOI: 10.3390/bios11080263] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/01/2021] [Accepted: 08/02/2021] [Indexed: 11/17/2022]
Abstract
Continuous microfluidic focusing of particles, both synthetic and biological, is significant for a wide range of applications in industry, biology and biomedicine. In this study, we demonstrate the focusing of particles in a microchannel embedded with glass grooves engraved by femtosecond pulse (fs) laser. Results showed that the laser-engraved microstructures were capable of directing polystyrene particles and mouse myoblast cells (C2C12) towards the center of the microchannel at low Reynolds numbers (Re < 1). Numerical simulation revealed that localized side-to-center secondary flows induced by grooves at the channel bottom play an essential role in particle lateral displacement. Additionally, the focusing performance proved to be dependent on the angle of grooves and the middle open space between the grooves based on both experiments and simulation. Particle sedimentation rate was found to critically influence the focusing of particles of different sizes. Taking advantage of the size-dependent particle lateral displacement, selective focusing of micrometer particles was demonstrated. This study systematically investigated continuous particle focusing in a groove-embedded microchannel. We expect that this device will be used for further applications, such as cell sensing and nanoparticle separation in biological and biomedical areas.
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Denis M, Bachoro M, Gebreslassie W, Oladunni T. Automatic Electrocardiogram Detection of Suspected Hypertrophic Cardiomyopathy: Application to Wearable Heart Monitors. IEEE Sens Lett 2021; 5:6001804. [PMID: 36313055 PMCID: PMC9610197 DOI: 10.1109/lsens.2021.3096382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
In this letter, an automatic detection algorithm for hypertrophic cardiomyopathy (HCM) is presented. Of particular interest is the algorithm's ability to differentiate HCM subjects and healthy volunteers from a single lead ECG dataset. Suspected HCM subjects are identified by the primary clinical abnormality associated with HCM: left ventricular hypertrophy (LVH). In total, n = 43 human subjects ECG datasets are investigated: n = 21 healthy volunteers and n = 22 LVH patients. Significant differences of p-value 0.01 and 0.04 were found for the respective ECG parameters, i.e., S-wave amplitude and ST-segment, when differentiating between the LVH patients and healthy human volunteers.
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Affiliation(s)
- Max Denis
- Department of Mechanical Engineering, University of the District of Columbia, Washington, DC 20008 USA
- Biomedical Engineering Program, University of the District of Columbia, Washington, DC 20008 USA
| | - Mulatu Bachoro
- Department of Mechanical Engineering, University of the District of Columbia, Washington, DC 20008 USA
- Biomedical Engineering Program, University of the District of Columbia, Washington, DC 20008 USA
| | - Winta Gebreslassie
- Department of Mechanical Engineering, University of the District of Columbia, Washington, DC 20008 USA
- Biomedical Engineering Program, University of the District of Columbia, Washington, DC 20008 USA
| | - Timothy Oladunni
- Department of Computer Science & Information Technology, University of the District of Columbia, Washington, DC 20008 USA
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Reyes-Ayona JR, Gallegos-Arellano E, Sierra-Hernández JM. Use of the Composite Properties of a Microwave Resonator to Enhance the Sensitivity of a Honey Moisture Sensor. Sensors (Basel) 2021; 21:s21072549. [PMID: 33917275 PMCID: PMC8038750 DOI: 10.3390/s21072549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 03/12/2021] [Accepted: 04/01/2021] [Indexed: 11/18/2022]
Abstract
A moisture sensor based on a composite resonator is used to measure different honey samples, which include imitation honey. The sensor changes its frequency response in accordance with the dielectric permittivity that it detects in the measured samples. Although reflectometry sensors have been used to measure the percentage of moisture in honey for almost a century, counterfeiters have achieved that their apocryphal product is capable of deceiving these kinds of sensors. Metamaterial features of the composite resonators are expected to improve their response when detecting lossy samples such as organic samples. It is also sought that these sensors manage to detect small differences not only in the real parts of the dielectric permitivities of samples but also in their imaginary parts, and, thus, the sensors are able to discern between real honey and slightly altered honey. Effectively, not only was it possible to improve the response of the sensors by using lossy samples but it was also possible to identify counterfeit honey.
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Affiliation(s)
- José R. Reyes-Ayona
- Telecommunication and Photonics Group, Electronics Department, Engineering Division of the Salamanca-Irapuato Campus, University of Guanajuato, Salamanca, Guanajuato 36885, Mexico; (J.R.R.-A.); (J.M.S.-H.)
| | - Eloisa Gallegos-Arellano
- Mechatronics Department, Technological University of Salamanca, Salamanca, Guanajuato 36766, Mexico
- Correspondence: ; Tel.: +52-464-647-3861
| | - Juan M. Sierra-Hernández
- Telecommunication and Photonics Group, Electronics Department, Engineering Division of the Salamanca-Irapuato Campus, University of Guanajuato, Salamanca, Guanajuato 36885, Mexico; (J.R.R.-A.); (J.M.S.-H.)
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Bianco GM, Marrocco G. Sensorized Facemask With Moisture-Sensitive RFID Antenna. IEEE Sens Lett 2021; 5:1-4. [PMID: 36789370 PMCID: PMC8768995 DOI: 10.1109/lsens.2021.3059348] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/08/2021] [Accepted: 02/11/2021] [Indexed: 06/15/2023]
Abstract
Due to the ongoing COVID-19 pandemic, the use of filtering facepiece respirators (FFRs) is increasingly widespread. Since the masks' wetness can reduce its filtering capabilities, the World Health Organization advises to replace the FFRs if they become too damp, but currently, there is no practical way to monitor the masks' wetness. A low-cost moisture sensor placed inside the FFRs could discriminate a slightly damp mask from a wet one, which must be replaced. In this letter, a radio frequency identification (RFID) tag exploiting an auto-tuning microchip for humidity sensing is designed and tested during an ordinary working day and a physical exercise. The tag returns about 1 unit of the digital metric every 3 mg of water generated by breathing and sweating, and it can identify excessively wet masks from commonly used ones.
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Affiliation(s)
- Giulio Maria Bianco
- Department of Civil Engineering and Computer Science EngineeringUniversity of Tor Vergata 00133 Roma Italy
| | - Gaetano Marrocco
- Department of Civil Engineering and Computer Science EngineeringUniversity of Tor Vergata 00133 Roma Italy
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Sarreal RR, Bhatti P. Characterization and Miniaturization of Silver-Nanoparticle Microcoil via Aerosol Jet Printing Techniques for Micromagnetic Cochlear Stimulation. Sensors (Basel) 2020; 20:E6087. [PMID: 33114773 DOI: 10.3390/s20216087] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/11/2020] [Accepted: 10/20/2020] [Indexed: 11/21/2022]
Abstract
According to the National Institute of Deafness and other Communication Disorders 2012 report, the number of cochlear implant (CI) users is steadily increasing from 324,000 CI users worldwide. The cochlea, located in the inner ear, is a snail-like structure that exhibits a tonotopic geometry where acoustic waves are filtered spatially according to frequency. Throughout the cochlea, there exist hair cells that transduce sensed acoustic waves into an electrical signal that is carried by the auditory nerve to ultimately reach the auditory cortex of the brain. A cochlear implant bridges the gap if non-functional hair cells are present. Conventional CIs directly inject an electrical current into surrounding tissue via an implanted electrode array and exploit the frequency-to-place mapping of the cochlea. However, the current is dispersed in perilymph, a conductive bodily fluid within the cochlea, causing a spread of excitation. Magnetic fields are more impervious to the effects of the cochlear environment due to the material properties of perilymph and surrounding tissue, demonstrating potential to improve precision. As an alternative to conventional CI electrodes, the development and miniaturization of microcoils intended for micromagnetic stimulation of intracochlear neural elements is described. As a step toward realizing a microcoil array sized for cochlear implantation, human-sized coils were prototyped via aerosol jet printing. The batch reproducible aerosol jet printed microcoils have a diameter of 1800 μm, trace width and trace spacing of 112.5 μm, 12 μm thickness, and inductance values of approximately 15.5 nH. Modelling results indicate that the coils have a combined depolarization–hyperpolarization region that spans 1.5 mm and produce a more restrictive spread of activation when compared with conventional CI.
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Fernández-Madrigal JA, Navarro A, Asenjo R, Cruz-Martín A. Characterization, Statistical Analysis and Method Selection in the Two-Clocks Synchronization Problem for Pairwise Interconnected Sensors. Sensors (Basel) 2020; 20:s20174808. [PMID: 32858927 PMCID: PMC7507003 DOI: 10.3390/s20174808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/07/2020] [Accepted: 08/14/2020] [Indexed: 11/22/2022]
Abstract
Time synchronization among sensor devices connected through non-deterministic media is a fundamental requirement for sensor fusion and other distributed tasks that need a common time reference. In many of the time synchronization methods existing in literature, the estimation of the relation between pairs of clocks is a core concept; moreover, in applications that do not have general connectivity among its devices but a simple pairwise topology, such as embedded systems, mobile robots or home automation, two-clock synchronization is actually the basic form of the time estimation problem. In these kinds of applications, especially for critical ones, not only the quality of the estimation of the relation between two clocks is important, but also the bounds the methods provide for the estimated values, and their computational effort (since many are small systems). In this paper, we characterize, with a thorough parameterization, the possible scenarios where two-clock synchronization is to be solved, and then conduct a rigorous statistical study of both scenarios and methods. The study is based on exhaustive simulations run in a super-computer. Our aim is to provide a sound basis to select the best clock synchronization algorithm depending on the application requirements and characteristics, and also to deduce which ones of these characteristics are most relevant, in general, when solving the problem. For our comparisons we have considered several representative methods for clock synchronization according to a novel taxonomy that we also propose in the paper, and in particular, a few geometrical ones that have special desirable characteristics for the two-clock problem. We illustrate the method selection procedure with practical use-cases of sensory systems where two-clock synchronization is essential.
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Affiliation(s)
| | - Angeles Navarro
- Department of Computer Architecture, University of Málaga, 29016 Málaga, Spain; (A.N.); (R.A.)
| | - Rafael Asenjo
- Department of Computer Architecture, University of Málaga, 29016 Málaga, Spain; (A.N.); (R.A.)
| | - Ana Cruz-Martín
- Department of System Engineering and Automation, University of Málaga, 29016 Málaga, Spain;
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Mikhalitsyna EA, Kataev VA, Larrañaga A, Lepalovskij VN, Kurlyandskaya GV. Nanocrystallization in FINEMET-Type Fe 73.5Nb 3Cu 1Si 13.5B 9 and Fe 72.5Nb 1.5Mo 2Cu 1.1Si 14.2B 8.7 Thin Films. Materials (Basel) 2020; 13:E348. [PMID: 31940894 DOI: 10.3390/ma13020348] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 01/09/2020] [Accepted: 01/10/2020] [Indexed: 11/17/2022]
Abstract
A growing variety of microelectronic devices and magnetic field sensors as well as a trend of miniaturization demands the development of low-dimensional magnetic materials and nanostructures. Among them, soft magnetic thin films of Finemet alloys are appropriate materials for sensor and actuator devices. Therefore, one of the important directions of the research is the optimization of thin film magnetic properties. In this study, the structural transformations of the Fe73.5Nb3Cu1Si13.5B9 and Fe72.5Nb1.5Mo2Cu1.1Si14.2B8.7 films of 100, 150 and 200 nm thicknesses were comparatively analyzed together with their magnetic properties and magnetic anisotropy. The thin films were prepared using the ion-plasma sputtering technique. The crystallization process was studied by certified X-ray diffraction (XRD) methods. The kinetics of crystallization was observed due to the temperature X-ray diffraction (TDX) analysis. Magnetic properties of the films were studied by the magneto-optical Kerr microscopy. Based on the TDX data the delay of the onset crystallization of the films with its thickness decreasing was shown. Furthermore, the onset crystallization of the 150 and 200 nm films began at the temperature of about 400–420 °C showing rapid grain growth up to the size of 16–20 nm. The best magnetic properties of the films were formed after crystallization after the heat treatment at 350–400 °C when the stress relaxation took place.
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Alex-Amor A, Moreno-Núñez J, Fernández-González JM, Padilla P, Esteban J. Parasitics Impact on the Performance of Rectifier Circuits in Sensing RF Energy Harvesting. Sensors (Basel) 2019; 19:s19224939. [PMID: 31766171 PMCID: PMC6891323 DOI: 10.3390/s19224939] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 11/04/2019] [Accepted: 11/06/2019] [Indexed: 11/16/2022]
Abstract
This work presents some accurate guidelines for the design of rectifier circuits in radiofrequency (RF) energy harvesting. New light is shed on the design process, paying special attention to the nonlinearity of the circuits and the modeling of the parasitic elements. Two different configurations are tested: a Cockcroft–Walton multiplier and a half-wave rectifier. Several combinations of diodes, capacitors, inductors and loads were studied. Furthermore, the parasitics that are part of the circuits were modeled. Thus, the most harmful parasitics were identified and studied in depth in order to improve the conversion efficiency and enhance the performance of self-sustaining sensing systems. The experimental results show that the parasitics associated with the diode package and the via holes in the PCB (Printed Circuit Board) can leave the circuits inoperative. As an example, the rectifier efficiency is below 5% without considering the influence of the parasitics. On the other hand, it increases to over 30% in both circuits after considering them, twice the value of typical passive rectifiers.
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Affiliation(s)
- Antonio Alex-Amor
- Departamento de Lenguajes y Ciencias de la Información, Universidad de Málaga, 29071 Málaga, Spain
- Information Processing and Telecommunications Center, Universidad Politécnica de Madrid, 28040 Madrid, Spain; (J.M.F.-G.); (J.E.)
- Correspondence:
| | - Javier Moreno-Núñez
- Departamento de Teoría de la Señal, Telemática y Comunicaciones, Universidad de Granada, 18071 Granada, Spain; (J.M.-N.); (P.P.)
| | - José M. Fernández-González
- Information Processing and Telecommunications Center, Universidad Politécnica de Madrid, 28040 Madrid, Spain; (J.M.F.-G.); (J.E.)
| | - Pablo Padilla
- Departamento de Teoría de la Señal, Telemática y Comunicaciones, Universidad de Granada, 18071 Granada, Spain; (J.M.-N.); (P.P.)
| | - Jaime Esteban
- Information Processing and Telecommunications Center, Universidad Politécnica de Madrid, 28040 Madrid, Spain; (J.M.F.-G.); (J.E.)
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Karayeğen G, Koçum IC, Çökeli Ler Serdaroğlu D, Doğan M. Aligned polyvinylpyrrolidone nanofibers with advanced electrospinning for biomedical applications. Biomed Mater Eng 2019; 29:685-697. [PMID: 30400080 DOI: 10.3233/bme-181017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Electrospinning is a highly effective method in order to generate nano-scaled fibers. In conventional electrospinning technique, geometry of nanofibers are mostly random due to the chaotic behavior of polymer jet. OBJECTIVE Purpose of this study is to produce aligned nanofibers from PVP polymers with advanced electrospinning technique in order to be used in a potential novel sensor applications, tissue regeneration and engineering. METHODS In this study, by using finite hollow cylinder focusing electrodes, an external electrostatic field is created. With these electrodes, it is aimed to decrease whipping instability of polymer jet. In addition, it is also investigated that the alignment ratio of nanofibers by using conductive parallel electrodes which placed through jet trajectory. RESULTS In conclusion, with the effect of electrical field created by cylinder electrodes, radius of the fiber dispersion on the collector was able to be reduced and aligned nanofibers were successfully produced by using electrical field generated from the parallel plates. CONCLUSIONS Radius of the fiber dispersion on the collector is 9.95 mm and fiber diameters varied between 800 nm and 3 μm. Additionally, alignment ratio of the fibers is determined with ImageJ software. These alignment of nanofibers can be used in tissue engineering applications and sensor applications.
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Affiliation(s)
- Gökay Karayeğen
- Department of Biomedical Equipment Technology, Başkent University, Bağlıca Campus, 06790 Ankara, Turkey
| | - I Cengiz Koçum
- Department of Biomedical Engineering, Başkent University, Bağlıca Campus, 06530 Ankara, Turkey
| | | | - Mustafa Doğan
- Deparment of Control and Automation Engineering, Istanbul Technical University, 34467 Istanbul, Turkey
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Lamas-Seco JJ, Castro PM, Dapena A, Vazquez-Araujo FJ. Vehicle Classification Using the Discrete Fourier Transform with Traffic Inductive Sensors. Sensors (Basel) 2015; 15:27201-14. [PMID: 26516855 PMCID: PMC4634484 DOI: 10.3390/s151027201] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 10/11/2015] [Accepted: 10/22/2015] [Indexed: 11/16/2022]
Abstract
Inductive Loop Detectors (ILDs) are the most commonly used sensors in traffic management systems. This paper shows that some spectral features extracted from the Fourier Transform (FT) of inductive signatures do not depend on the vehicle speed. Such a property is used to propose a novel method for vehicle classification based on only one signature acquired from a sensor single-loop, in contrast to standard methods using two sensor loops. Our proposal will be evaluated by means of real inductive signatures captured with our hardware prototype.
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Affiliation(s)
- José J Lamas-Seco
- Grupo de Tecnoloxía Electrónica e Comunicacións (GTEC), Departamento de Electrónica e Sistemas, Facultade de Informática, Universidade da Coruña, Campus da Coruña, 15071 A Coruña, Spain.
| | - Paula M Castro
- Grupo de Tecnoloxía Electrónica e Comunicacións (GTEC), Departamento de Electrónica e Sistemas, Facultade de Informática, Universidade da Coruña, Campus da Coruña, 15071 A Coruña, Spain.
| | - Adriana Dapena
- Grupo de Tecnoloxía Electrónica e Comunicacións (GTEC), Departamento de Electrónica e Sistemas, Facultade de Informática, Universidade da Coruña, Campus da Coruña, 15071 A Coruña, Spain.
| | - Francisco J Vazquez-Araujo
- Grupo de Tecnoloxía Electrónica e Comunicacións (GTEC), Departamento de Electrónica e Sistemas, Facultade de Informática, Universidade da Coruña, Campus da Coruña, 15071 A Coruña, Spain.
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