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It is known that manually detecting heart conditions is often costly and time-consuming and any study regarding diagnose these conditions has a great importance. In this study, a metaheuristic optimization model has been developed to automate the detection of heart diseases with artificial intelligence compatible methods. In the proposed model, the feature set is selected to represent the best heart sound signals and heart disease diagnoses using machine learning algorithms with these feature sets. The proposed method has been tested on the Pascal dataset which consists of four classes. Firstly, an electronic-based filter model is used as low-pass filter and has great potential to use as a filtering for heart sound signals to decrease noise. Secondly, the statistical and acoustic feature vector extracted from the audio signals in the Pascal dataset is passed through particle swarm optimization (PSO), firefly algorithm (FA) and cuckoo search algorithm (CSA), and the most suitable feature vector is selected. After obtaining the most suitable feature vector with metaheuristic optimization algorithms and filtering method, heart disease diagnosis is performed using random forest (RF), K-nearest neighbor (K-NN), support vector machine (SVM) and Naive Bayes machine learning algorithms. [ABSTRACT FROM AUTHOR]

During geomagnetic storms, the capabilities of current climate models in predicting ionospheric behavior are notably limited. A data assimilation tool, Estimating Model Parameters Reverse Engineering (EMPIRE), implements a Kalman filter to ingest electric density rate correcting the background electric potential and neutral wind. For the baseline setup, or case (1), EMPIRE ingests electron density global map output from the Ionospheric Data Assimilation 4‐Dimensional (IDA4D) algorithm. In this work, a new augmentation method is evaluated in which ion drift measurements are also assimilated into EMPIRE. The ion drift measurements used in the new augmentation method are obtained from Super Dual Auroral Radar Network (SuperDARN) sites in the mid‐to‐high latitude region of the northern hemisphere. Cases (2) and (3) are set up for evaluating the impacts from ingesting different types of observations: SuperDARN fit and grid data, respectively. Six independent data sources are used as validation data sets to compare outcomes with or without ingesting ion drifts. One is the vector ion velocities derived from the Millstone Hill Incoherent Scatter Radar (MHISR) and a second is the vertical drift from Arecibo site. The other four are SuperDARN ion velocity grid data from Saskatoon, Kapuskasing, Christmas Valley West, and Hokkaido East. Results show improvements in performance at mid‐latitudes by augmenting electron density rates with 3D spatially distributed line‐of‐sight ion drift measurements, with negligible improvements to low and high latitude estimations. The lack of improvement at high‐latitudes is attributed to the increase in EMPIRE ion drift error poleward of 60° magnetic. Plain Language Summary: Current climate models struggle to accurately predict changes in the ionosphere especially during geomagnetic storm time. A data assimilation system is implemented to improve the prediction of upper atmospheric drivers by incorporating measurement information of electron density in a global setting. This study introduces a new method that also includes ion drift measurements at the mid‐to‐high latitudes. Six independent data sets are compared to the results from the original and new experimental setups, and we investigate how the accuracy of our prediction is affected by the amount of pre‐processing of measurements before they are used. We find that ion motion measurements improve mid‐latitude ion drift estimations when more ion drift information is added to the DA system but no significant improvements at low and high latitudes. Key Points: We augment a data assimilation algorithm to ingest fit and gridded ion velocity data from the Super Dual Auroral Radar Network (SuperDARN)We compare the new augmentation results with the primary setup of only ingesting electron density ratesAssimilation of distributed line‐of‐sight fit drifts at high latitudes yields improvement at magnetic mid‐latitudes [ABSTRACT FROM AUTHOR]

In this paper, a dual-bandstop frequency-selective surface (FSS) implemented using a four-legged Minkowski square and s hexagonal ring is presented. The proposed FSS shows dual stopbands at 4.9 GHz and 7.1 GHz in the C band. The size of the unit cell is 0.36λ0 × 0.36λ0, which is designed on an FR4 substrate with a thickness of 1.6 mm and a loss tangent of 0.02. The frequency response of the bandstop FSS is verified using circuit simulation, and its optimised dimensions are determined at the desired frequencies of operation. The results reveal that the ratio of the two stopband frequencies can be adjusted over a wide range by properly selecting the geometrical parameters. The impedance bandwidths for S11< –10 dB of 0.9 GHz and 1 GHz have been realised at the lower and upper frequency bands, respectively. A prototype is fabricated and measurements show a reasonable agreement with the simulated results, thus validating the design concept. It has been shown that the proposed bandstop FSS exhibits excellent stability upto 60° at oblique incident angles in both TE and TM polarisations. This FSS is suitable for C-band maritime applications due to wide stopbands and highly stable angular operation. [ABSTRACT FROM AUTHOR]

The paper proposes an innovative model able to predict the output signals of resistance and capacitance (RC) low-pass filters for machine-controlled systems. Specifically, the work is focused on the analysis of the parametric responses in the time- and frequency-domain of the filter output signals, by considering a white generic noise superimposed onto an input sinusoidal signal. The goal is to predict the filter output using a black-box model to support the denoising process by means of a double-stage RC filter. Artificial neural networks (ANNs) and random forest (RF) algorithms are compared to predict the output of noisy signals. The work is concluded by defining guidelines to correct the voltage output by knowing the predictions and by adding further RC elements correcting the distorted signals. The model is suitable for the implementation of Industry 5.0 Digital Twin (DT) networks applied to manufacturing processes. [ABSTRACT FROM AUTHOR]

This paper presents a new circuit approach to realize a capacitance multiplier circuit with positive and negative multiplication factors. Based on this approach, two new implementations of positive and negative grounded capacitance multiplier (GCM) circuits are proposed, which utilize only one current follower differential input transconductance amplifier (CFDITA), in conjunction with only one resistor and one virtually grounded capacitor. The presented GCM circuits can enhance a low capacitance value to a very high value (used in low frequency applications), up to 9202 times its original value. An important aspect of the proposed circuits involves designing a lossy parallel inductor circuit by interchanging the passive elements (RC:CR transformation) with each other. The obtained value of the capacitance and inductance can be controlled independently and electronically through the transconductance of CFDITA. The practical usability of the suggested circuits as first and second order filters is discussed. The functionality of the proposed GCM circuits is validated using CMOS CFDITA implemented with 180 nm TSMC technology parameters. Experimental verification of the proposed circuits and application examples is reinforced through the utilization of CFDITA implemented with readily available ICs AD844 and LM13700. These outcomes emphasize the dependability of the suggested circuits. [ABSTRACT FROM AUTHOR]

Accurate and fast estimation of the state of charge is important for the battery management system of electric vehicles. This paper proposes a method to estimate the state of charge of Lithium-ion batteries by the variable forgetting factor recursive least square (VFFRLS) - unscented Kalman filter (UKF) algorithm in real-time without the off-line battery testing data. Since the state observation requires an accurate model, an equivalent circuit model was constructed. Then, the VFFRLS algorithm is used to identify online the battery model parameters based on voltage and current measurements. An advantage of this algorithm is that it requires less initial information and shorter identification time than offline parameter identification. After the model parameters are well identified, the unscented Kalman filter estimates the state of charge and minimizes noise characteristics and uncertainty in the parameter identification process. The VFFRLS algorithm applied in this paper has shown a good result with the model output error of less than 1%, and the identification achieves real-time response. The state of charge obtained by the UKF algorithm has shown satisfactory estimation results with fast convergence speed and small errors. The UKF filter provides the results with a 1.5% error from the reference and converges after 10 cycles. [ABSTRACT FROM AUTHOR]

This paper presents a novel multiple-input and multiple-output current-mode universal analog filter with electronic tuning capability. The proposed circuit uses a single second-generation current-controlled current conveyor with extra-X terminals (EX-CCCII) and two grounded capacitors. The filter can offer five standard filtering functions, namely low-pass, high-pass, band-pass, band-stop, all-pass responses, in the same circuit without changing the internal configuration of the filter by selecting appropriate input and output signals. To obtain the five standard filtering functions, inverted input signal and input matching conditions are absent. The natural frequency of all filter responses can be electronically controlled. The proposed circuit was simulated by SPICE using 0.18 μm CMOS process from Taiwan Semiconductor Manufacturing Company (TSMC). The results of experiments using the integrated circuit operational amplifier AD844 confirm the functionality of the new filter. [ABSTRACT FROM AUTHOR]

The acousto-optic characteristics of a paratellurite crystal with a cut angle of α = 10.2° have been investigated theoretically and experimentally. The crystal is used in an acousto-optic filter for processing optical images in visible and infrared light. The electric range of filter tuning has been experimentally determined based on the frequency dependence of the power absorbed by the piezoelectric transducer of the filter. Estimates of the range of filter tuning with respect to optical wavelengths are made. At light wavelengths of λ = 1.15 µm and λ = 0.63 µm, the dependences of the Bragg angle of incidence on the ultrasound frequency are calculated. When measuring the diffraction efficiency in the deflector operation mode, it was found that the range of filter tuning in optical wavelengths turns out to be different from that predicted as a result of measuring the electrical characteristics of the transducer and becomes narrower. [ABSTRACT FROM AUTHOR]

The novel aromatic cyclic compound type of crystals such as AMPF as 2-amino-4-methylpyridinium fumarate are properly grown by slow evaporation method; the grown crystals are analyzed for single crystalline X-ray diffraction study with the lattice constants as a, b, c with 5.0234 Å; 20.0146 Å; 10.8852 Å and β as 95.767° and are grown at room temperature; the crystal is with volume as 1094.41Å3; crystal system is monoclinic and is of P21/n as space group. The computational study portrays and delineates the AMPF with unit cell and the Laue's pattern of both ways and also with that of the ORTEP – the thermal ellipsoidal plot for proper projection in the atomic scaling. The dielectric behavior of the material is analyzed for pure macro level scaling and is high dielectric constant – εr and Conductivity – σac with less dielectric loss factors prefer the use of AMPF crystals in the field of opto-electronic and µ-electronic engineering usage. The µ-influx of 4.9691 microns properly portrays for electronic filtering application of AMPF and is asserted and implemented as a better candidate in voltage regulation processing. [ABSTRACT FROM AUTHOR]

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper introduces a new simple moment-generating function (MGF) design modelling method to conclude an optimum filter to maximize the Q-factor and increase the link communication span. This approach mitigates the pulse temporal dispersion, particularly the underwater wireless optical communication (UWOC) systems. Hence, some form of equalizing filter design is highly desirable. The model solution environment includes a Double Gamma Function (DGF) water channel impulse response, intersymbol interference (ISI), stochastic Poisson process, and additive Gaussian thermal noise (AGTN). The optimal filters exhibit temporal profiles comparable to those derived by published works based on complex Chernoff Bound (CB) and Modified Chernoff Bound (MCB) methods. The results show the impact of the optimum filter at a signal level and optical receiver level utilizing Eye-Diagrams and BER vs. Q-Factor, respectively. The computation involves four different UWOC propagation channel models for Coastal and Harbor waters. One of the main conclusions indicates that the optimum filter manages the temporal dispersion due to the ISI impairment correctly. Also, the proposed optimum filter reduces eye-opening and the corresponding Q-Factor by less than 15% for a five-times increase in pulse width for the same transmitted optical power level. [ABSTRACT FROM AUTHOR]

Purpose: Fixed mode noise and random mode noise always exist in the image sensor, which affects the imaging quality of the image sensor. The charge diffusion and color mixing between pixels in the photoelectric conversion process belong to fixed mode noise. This study aims to improve the image sensor imaging quality by processing the fixed mode noise. Design/methodology/approach: Through an iterative training of an ergoable long- and short-term memory recurrent neural network model, the authors obtain a neural network model able to compensate for image noise crosstalk. To overcome the lack of differences in the same color pixels on each template of the image sensor under flat-field light, the data before and after compensation were used as a new data set to further train the neural network iteratively. Findings: The comparison of the images compensated by the two sets of neural network models shows that the gray value distribution is more concentrated and uniform. The middle and high frequency components in the spatial spectrum are all increased, indicating that the compensated image edges change faster and are more detailed (Hinton and Salakhutdinov, 2006; LeCun et al., 1998; Mohanty et al., 2016; Zang et al., 2023). Originality/value: In this paper, the authors use the iterative learning color image pixel crosstalk compensation method to effectively alleviate the incomplete color mixing problem caused by the insufficient filter rate and the electric crosstalk problem caused by the lateral diffusion of the optical charge caused by the adjacent pixel potential trap. [ABSTRACT FROM AUTHOR]

With the recent conversion of internal combustion engines to electric vehicles, new noise issues have arisen, and among them, the noise generated by internal vehicle auxiliary systems is being considered. This study introduces an electronic filter designed with a motor model featuring vibration components, aiming to minimize the noise and vibrations generated by a Brushed DC (BDC) motor commonly employed in vehicle internal systems. It introduces a method to identify the connectors and internal parameters used in the motor for the matching of the model and experimental motor, and to measure and estimate these parameters. The model is separated and executed to ensure convergence, and it is validated by comparing the analysis results with the measured values. A filter is designed using the model to reduce current oscillations in the motor, confirming a subsequent reduction in noise and vibration. This research suggests the potential to attenuate noise and vibration in already produced motors by attaching only a filter without modifying the internal motor structure. Moreover, it is anticipated that a filter can be designed to predict and mitigate the noise and vibration components of the motor based on changes in load. [ABSTRACT FROM AUTHOR]

Introduction and Purpose: Nonlinear modal coupling via internal resonances and parametric excitation in MEMS resonators has been widely used to improve the functionality and performance of a wide range of potential applications. In this paper, the bandpass filter based on a 2:1 internal resonance between the second and third modes of a clamped-guided microbeam with electrostatic activation is proposed for the first time. Due to internal resonance, the amplitude–frequency response of the second mode showed a rectangle-like bandpass behaviour when the third mode is externally excited around the resonance by sweeping external excitation frequency. Methods: In this study, numerical time integration and the method of multiple scales are used to confirm the bandpass characteristics in the amplitude–frequency response curve of the second mode of the beam. Results: The computational results showed that the mid-plane stretching nonlinearity, excitation amplitude, and damping have a significant impact on the bandpass behaviour. We also presented the centre frequency and 3 dB bandwidth of the filter as a function of the mid-plane stretching nonlinearity parameter and a combination of excitation amplitude and damping. Moreover, we found the bandpass frequency bandwidth 261.64−1130 Hz for various axial excitation amplitude and damping combinations using a particular beam dimension and material properties from the literature. Specifically, the bandpass filter exhibited a 3 dB bandwidth of 954.97 Hz with a centre frequency of 143.09 kHz for a set of beam dimensions and material properties. Conclusions: The internal resonance-based bandpass filter demonstrated here illustrates a novel method for building filters using a single MEMS resonator. Here, we consider electrostatically actuated clamped–guided beams, but the concept can be applied to any MEMS resonator that exhibits modal coupling based on internal resonance. In addition, it is more durable than contemporary electronic filters and is temperature-robust. The work presented here might potentially serve as a guide for investigating more MEMS resonators to create bandpass filters based on internal resonances. [ABSTRACT FROM AUTHOR]

This work introduces and examines a new programmable electronic system, Board ADF339, designed for filtering analog measurement signals of low frequencies. The system operates in a mixed mode in collaboration with a digital controller implemented on the myRIO-1900 FPGA module. It enables the digital selection of the type and frequency settings of the UAF42 integrated circuit. In the technical implementation section, electronic filter and phase shifter circuit diagrams are presented, along with the digital counterpart of the analog filter. Tests of this system were conducted on signals generated using a function generator, which was followed by the filtration of signals occurring in real laboratory setups. A series of real responses from three different laboratory systems and a measurement system utilizing LabVIEW FPGA virtual instruments are demonstrated. After computing SNR indicators for noisy waveforms, the application scope and usability of the board are highlighted. [ABSTRACT FROM AUTHOR]

First-order allpass filters are analog filters with a unit magnitude response, but they change the phase shift between input and output signals at various frequencies. This paper presents the transadmittance-mode first-order allpass filters based on the modified current-controlled current differencing transconductance amplifier (M-CCCDTA). The proposed filters utilize a single M-CCCDTA and a grounded capacitor with no external resistors, making them well suited for implementation in an integrated circuit. The gain and phase response of the proposed filters can be adjusted electronically and separately. Also, the high output impedance of the proposed filters at both the input voltage node and the output current node makes cascading easy without the need for buffer devices. A quadrature sinusoidal oscillator based on the proposed first-order allpass filter has been designed as an example of an application. The PSpice simulation and actual experiments are utilized to validate the functionality of the proposed filters. The simulation and experimental results are consistent with the idea of anticipation. [ABSTRACT FROM AUTHOR]

With the stricter emission regulations for internal combustion engines, electric vehicles, including electrically powered port tractors, have received increasing attention. However, currently, most of the filters used in electric vehicles are conventional membranes that only have the function of filtering particles and foreign objects. Therefore, in order to improve the above issues, the surface of commercial non-woven filter membranes was coated with Ag nanopowder nanofibers and AgNO3 nanofibers via electrospinning. At present, the comparative research on the antibacterial ability of Ag nanopowder and AgNO3 is still blank in the same research system, especially with the use of electrospun coating technology. The morphologies and structures of non-woven fabrics and electrospinning coated samples were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The characterization results indicate that both pure PVA and PVA composite fibers can be successfully coated on the surface of non-woven fabrics. The average diameter of all electrospun PVA composite fibers is distributed in the range of 470–700 nm. The PVA nanofibers with a low content of 1 wt% AgNO3 have good antibacterial properties against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), with clearance clear zones of inhibition of 26.00 mm and 17.30 mm, respectively. [ABSTRACT FROM AUTHOR]

A differential magnetic field probe based on a balanced filter is proposed to improve electric field suppression. The probe comprises a rectangular metal loop for detection and a balanced filter transmission. Three 1/4λ stepped impedance transmission lines are designed between the detective part and balanced filter for impedance matching. The balanced filter can suppress the common mode signals generated by a normal electric field but has little influence on the differential signals detected by a tangential magnetic field thus, the electric field suppression of the magnetic probe can be enhanced. The measurement results show that the working frequency of the proposed magnetic probe ranges from 10 to 20 GHz, and the electric field suppression ratio is over 35 dB from 10 to 15 GHz. [ABSTRACT FROM AUTHOR]

This paper presents the design and application of a boost converter operated in continuous conduction mode for 15 W, with a 25 kHz switching frequency using an inductor-capacitor-inductor (LCL), pi, inductor capacitor (LC) with damping, and LC electromagnetic interference filters. Also, modeling and analysis of the boost converter in terms of state space and small signal are given. Furthermore, the effect of each filter on differential mode (DM) noise and control characteristics is presented using root locus and bode diagrams, which are not detailed in the literature for the boost converter. All results obtained from applications and simulations are compared. Moreover, frequency spectrums are given to compare DM noises. As a result, from a control point of view, the LCL filter provides better results, and for reducing DM noise, the LC and pi filters are superior to others. Besides, the LCL filter reduces the inductor value by 30% compared to other filters. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Cochlear implant (CI) and electric-acoustic stimulation (EAS) users may experience better performance with maps that align the electric filter frequencies to the cochlear place frequencies, known as place-based maps, than with maps that present spectrally shifted information. Individual place-based mapping procedures differ in the frequency content that is aligned to cochlear tonotopicity versus discarded or spectrally shifted. The performance benefit with different place-based maps may vary due to individual differences in angular insertion depth (AID) of the electrode array and whether functional acoustic low-frequency information is available in the implanted ear. The present study compared masked speech recognition with two types of place-based maps as a function of AID and presence of acoustic low-frequency information. Methods: Sixty adults with normal hearing listened acutely to CI or EAS simulations of two types of place-based maps for one of three cases of electrode arrays at shallow AIDs. The strict place-based (Strict-PB) map aligned the low- and mid-frequency information to cochlear tonotopicity and discarded information below the frequency associated with the most apical electrode contact. The alternative place-based map (LFshift-PB) aligned the mid-frequency information to cochlear tonotopicity and provided more of the speech spectrum by compressing low-frequency information on the apical electrode contacts (i.e., <1 kHz). Three actual cases of a 12-channel, 24-mm electrode array were simulated by assigning the carrier frequency for an individual channel as the cochlear place frequency of the associated electrode contact. The AID and cochlear place frequency for the most apical electrode contact were 460° and 498 Hz for case 1, 389° and 728 Hz for case 2, and 335° and 987 Hz for case 3, respectively. Results: Generally, better performance was observed with the Strict-PB maps for cases 1 and 2, where mismatches were 2–4 octaves for the most apical channel with the LFshift-PB map. Similar performance was observed between maps for case 3. For the CI simulations, performance with the Strict-PB map declined with decreases in AID, while performance with the LFshift-PB map remained stable across cases. For the EAS simulations, performance with the Strict-PB map remained stable across cases, while performance with the LFshift-PB map improved with decreases in AID. Conclusions: Listeners demonstrated differences with the Strict-PB versus LFshift-PB maps as a function of AID and whether acoustic low-frequency information was available (CI vs. EAS). These data support the use of the Strict-PB mapping procedure for AIDs ≥335°, though further study including time for acclimatization in CI and EAS users is warranted. [ABSTRACT FROM AUTHOR]

This study investigates alternating current barrier discharges in Townsend, glow, and arc modes when the barrier constitutes a semiconductor. First, the electrical characteristics of the reactor, with a specific electrode configuration, and the effect of the semiconductor on plasma formation are examined. Subsequently, the surface and structure of the semiconductor barriers, processed for the three modes, are analyzed at an atomic scale. The results indicate that the plasma produced within the semiconductor barrier discharge (SBD) system exhibits higher homogeneity. Notably, the barrier is active in the Townsend mode. In proportion to the voltage applied to the SBD system, the semiconductor diminishes its barrier property, and the influence of the semiconductor barrier loses upon reaching approximately 1 kV. The plasma becomes inhomogeneous in arc mode, and strong current channels become prominent, leading to substantial degradation of the semiconductor barrier. Furthermore, the proposed electrode configuration presents properties characteristic of a Schottky diode. Ultimately, the electrical equivalent circuit of the reactor demonstrates similarities with a varactor structure. The SBD system's electronic structure and filtering feature could potentially contribute to the future conception of self-controlled BD systems. [ABSTRACT FROM AUTHOR]

The design of a low-pass-frequency filter with the electronic change of the approximation characteristics of resulting responses is presented. The filter also offers the reconnection-less reconfiguration of the order (1st-, 2nd-, 3rd- and 4th-order functions are available). Furthermore, the filter offers the electronic control of the cut-off frequency of the output response. The feature of the electronic change in the approximation characteristics is investigated for the Butterworth, Bessel, Elliptic, Chebyshev and Inverse Chebyshev approximations. The design is verified by PSpice simulations and experimental measurements. The results are also supported by the transient domain response (response to the square waveform), comparison of the group delay, sensitivity analysis and implementation feasibility based on given approximation. The benefit of the proposed electronic change in the approximation characteristics feature (in general signal processing or for sensors in particular) is presented and discussed for an exemplary scenario. [ABSTRACT FROM AUTHOR]

This paper proposes a new type of hybrid eighth‐mode substrate integrated waveguide (EMSIW) and microstrip line (MSL) bandpass filter (BPF) with mixed electric and magnetic coupling. Firstly, two second‐order EMSIW BPFs with mixed coupling and wide stopband performance are investigated. Then, in order to realise high‐order BPF with decent performance, half‐wavelength (λ/2) open‐circuited MSL resonators are employed in the hybrid BPFs design. In the end, two third‐order BPFs and a fourth‐order BPF are developed by combining the EMSIW and MSL resonators together. Extra transmission zeros can be introduced due to the cross couplings in the trisection and quadruplet topologies. For demonstration, the proposed prototypes are designed, fabricated and measured. Reasonable agreements can be achieved between the measurement and simulation. The proposed third‐order BPFs compete against the state of the art, exhibiting the competitive characteristics of the operating bandwidth, physical footprint and upper‐stopband rejection with less order. The proposed fourth‐order BPF features a compact size of 0.34 × 0.34λ0, a low insertion loss of 1 dB, a broad 3‐dB fractional bandwidth of 22.9% and an excellent lower‐stopband suppression. [ABSTRACT FROM AUTHOR]

To avoid damaging the motor and its surrounding equipment, detecting Inter-Turn Short Circuit (ITSC) faults in Permanent Magnet Synchronous Motors (PMSMs) applied in electric vehicles is a crucial task. In this paper, the detection of ITSC faults in stator winding for PMSMs is carried out by means of the Extended KALMAN Filter (EKF) algorithm combined with the Fuzzy Logic Estimator (FLE). To estimate the motor parameters, including the rotor position and speed, the EKF algorithm uses the measured stator currents and voltages beside the stator resistance, which is calculated in advance using fuzzy logic and fed to the EKF. The change behaviors of the estimated parameters were then used to detect short circuit faults in the PMSM. Using Matlab/Simulink, the proposed FL-EKF algorithm was implemented and tested on a faulty PMSM controlled by Field Oriented Control (FOC). The observation of a perfect estimation of the stator resistance through the simulation helps to precisely detect the failure, and that demonstrates the sensitivity and robustness of the proposed approach. [ABSTRACT FROM AUTHOR]

The single crystalline diethyl 3,3 ′ -[(2,4-dichlorophenyl)methylidene]bis(1H-indole-2-carboxylate) (D32DMBC) samples are fully grown-up in a proper and in a successful manner by the prevailing slowly evaporating methodology. The lattice cell frameworks by XRD modus operandi also corroborated that the D32DMBC crystal system is monoclinic in nature. The structural properties by a conceptual way authenticate the elucidation and also the proper vindication for bond parameters. The nano influx is 3.2768 micron and the film-coated influx of 2.9977 microns as a mid-value between the macro as well as the nano assessment is suitable for electronic filters by D32DMBC crystals, and also used for tribological-coated utility as well as in frequency multipliers. Diabetes mellitus is the repetitive disease in the way of life and sustaining approach of D32DMBC — organic crystals are properly, accurately experimented by the use of the software pertaining to the D32DMBC by docking effect. The affinity inhibitory activity of A74DME and exploratory molecule of D32DMBC are −8.1 kJ/mole and −8.4 kJ/mole correspondingly. The computational effect of Hirshfeld portrays the internal/external fields as well as the electron higher/lower profile in the shape index proviso for optical utility identification and proper electronic utility. [ABSTRACT FROM AUTHOR]

Electrocardiogram (ECG) signals are often measured for medical purposes and in sports. While common Ag/AgCl glued gel electrodes enable good electrode skin contact, even during movements, they are not comfortable and can irritate the skin during long-term measurements. A possible alternative is textile electrodes, which have been investigated extensively during the last years. These electrodes, however, are usually not able to provide reliable, constant skin contact, resulting in reduced signal quality. Another important problem is the modification of the electrode surface due to washing or abrasion, which may impede the long-term use of such textile electrodes. Here, we report a study of washing and abrasion resistance of different ECG electrodes based on an isolating woven fabric with conductive embroidery and two conductive coatings, showing unexpectedly high abrasion resistance of the silver-coated yarn and optimum ECG signal quality for an additional coating with a conductive silicone rubber. Sheet resistances of the as-prepared electrodes were in the range of 20–30 Ω, which was increased to the range of 25–40 Ω after five washing cycles and up to approximately 50 Ω after Martindale abrasion tests. ECG measurements during different movements revealed reduced motion artifacts for the electrodes with conductive silicone rubber as compared to glued electrodes, suggesting that electronic filtering of such noise may even be easier for textile electrodes than for commercial electrodes. [ABSTRACT FROM AUTHOR]

This paper presents a design methodology that significantly increases the peak power handling capability (PPHC) of microstrip filters. The PPHC is limited in microstrip technology by the corona effect: a physical phenomenon caused by the ionization of the air in the presence of strong electric fields around the planar circuit. Microstrip filter with low electric field strength in the air increases the corona threshold level, resulting in high PPHC. Conventional stepped impedance (SI) filters, which consist of cascaded step-shaped elements, exhibit sharp discontinuities. These geometric edges amplify the electric field strength in the air, consequently reducing the corona threshold. Our research group has recently reported a new synthesis technique that introduces a smooth-profile (SP) conductor strip. This SP strip eliminates any sharp discontinuities and significantly reduces the strength of the electric field. This paper focuses on the examination of the high power performance of 7th-order SP and SI low-pass filters. The cut-off frequency (fc) for both types of filters is set at 447.45 MHz, while the frequency for maximum stop-band rejection (fo) is 1 GHz. The findings indicate that the SP filter shows a notable enhancement in peak power handling capability (PPHC), with gains of 2.48 dB and 4.80 dB observed at critical pressure and ambient pressure, respectively. [ABSTRACT FROM AUTHOR]

This article presents a tunable fourth-order band-pass filter that is designed using operational transconductance amplifier (OTA), which can be used as an anti-aliasing filter (AAF) in the front-end of an analog to digital converter (ADC). It is necessary to use a suitable filter to prevent unwanted signals from entering the ADC. The bandwidth of the AAF should be designed according to the bandwidth of the ADC, therefore, matching these two bandwidths is one of the important challenges when using multi-bandwidth analog to digital converters in the digital communication applications. The proposed band-pass filter is designed and simulated in 180nm CMOS technology. The simulation results show that by changing the two bias voltages of the proposed filter, its bandwidth can be changed according to the frequency range of ADSL, ADSL2 and ADSL2+ communication standards and it effectively attenuates unwanted signals. [ABSTRACT FROM AUTHOR]

High‐Field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS) utilizes the characteristics of nonlinear ion mobility at high electric fields to filter ions. We propose a novel glass‐cell FAIMS olfactory sensor that mimics the olfactory sense of living organisms by applying LCD mass production process technology. This olfactory sensor has a simple configuration consisting of an odor molecule ionization section and a glass‐cell FAIMS sensor, which is a pair of glass substrates with patterned electrodes. The ionized odor molecules pass through the glass‐cell FAIMS sensor, and the filtered ion molecules are detected. We have experimented with different odorous components, including fermented beverages (wine) and animal excrement (cat urine, stool), to create unique "odor fingerprints". [ABSTRACT FROM AUTHOR]

In cognitive communications, it is very important to be able to use data in different standards with a single receiver for reducing the cost. In order to achieve this, the application of shadow filters in cognitive communications provides an advantage in terms of having both a wide frequency range and an easy reconfiguration. In this paper, new MOSFET-C shadow filters based on the Fully Differential Second-Generation Current Conveyor (FDCCII) are proposed for cognitive communications. To facilitate electronic tuning of the filter parameters, MOSFET-C-based implementation is used. Fully differential applications increase the dynamic range of analog blocks. Also, fully differential implementations with MOSFET-C filters are useful in analog signal processing. The presented filters have the least number of components and no additional summing circuit. This study presents new FDCCII-based MOSFET-C shadow filters for cognitive communications design that provide HP, LP and BP transfer functions at the same time. In this study, two MOSFET-C shadow filters based on FDCCII are designed for single gain and double gain. The presented filters offer circuit simplicity compared to past shadow filter designs. The features of these new shadow filters are explained. Simulation results are presented to confirm the theoretical analysis. [ABSTRACT FROM AUTHOR]

Three events are presented where high‐resolution measurements from the Swarm satellites coincided with excellent F‐region ionospheric coverage from The Super Dual Auroral Radar Network (SuperDARN). Large‐scale ionospheric convection patterns from SuperDARN, together with field‐aligned‐current patterns from he Active Magnetosphere and Planetary Response Experiment (AMPERE), provide information on quasi‐static ionospheric dynamics traversed by Swarm. Because the Swarm observations and orbital path coincided with favorable SuperDARN/AMPERE observing conditions, it was possible to filter the Swarm electric field observations into a quasi‐static component that agreed with the SuperDARN electric field. The residual electric field from Swarm is thus indicative of small‐ and mesoscale dynamics not captured by the convection and field‐aligned current (FAC) patterns. Calculations of the Poynting flux between the different instruments show that dynamics on small‐to mesoscales can be highly variable within structures like FACs. In the events shown, small‐ and medium‐scale Poynting fluxes occasionally dominate over those from large‐scale processes. Plain Language Summary: A significant amount of energy from the solar wind deposited into the upper atmosphere of Earth (above ∼100 km altitude) is contained within small‐scale (on the order of kilometers) fluctuations of the electric field. This kind of variability is difficult to measure do the sparse resolution (both in space and time) of instruments like ground‐based instruments, or the global fitting procedures of satellite constellations. Those instruments, which tend to focus on observing large‐scale "big picture" dynamics, do however excel at providing important information about the global state of the upper atmosphere. Small‐scale (∼1 km) data from the Swarm satellites is used in this letter, in conjunction with ground‐based radars and a satellite constellation, to obtain a complete picture of how space weather energy dissipation is spread across all scale sizes. It is found that small features that only Swarm can see occasionally dominate in terms of energy balance. Key Points: Filtered electric fields from the Swarm satellites agree with SuperDARNVariable and high‐magnitude Poynting flux structures are embedded in and between field‐aligned currentsPoynting flux from sub‐quasi‐static dynamics can comprise as much as half of the total [ABSTRACT FROM AUTHOR]

Background: Dynamic myocardial computed tomography perfusion (CTP) is a novel technique able to depict cardiac ischemia. Purpose: To evaluate the impact of a four-dimensional noise reduction filter (similarity filter [4D-SF]) on image quality in dynamic CTP imaging, allowing for substantial radiation dose reduction. Material and Methods: Dynamic CTP datasets of 30 patients (16 women) with suspected coronary artery disease, acquired with a 320-slice CT system, were retrieved, reconstructed with the deep learning-based algorithm of the system (DLR), and filtered with the 4D-SF. For each case, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in six regions of interest (33–38mm2) were calculated before and after filtering, in four-chamber and short-axis views, and t-tested. Furthermore, six radiologists of different expertise evaluated subjective image preference by answering five visual grading analysis-type questions (regarding acceptable level of noise, absence of artifacts, natural appearance, cardiac contour sharpness, diagnostic acceptability) using a 5-point scale. The results were analyzed using visual grade characteristics (VGC) and intraclass correlation coefficient (ICC). Results: Mean SNR in four-chamber view (unfiltered vs. filtered) were: septum=4.1 ± 2.1 versus 7.6 ± 5.6; lateral wall=4.5 ± 2.0 versus 8.0 ± 4.9; CNRseptum=16.6 ± 8.9 versus 31.7 ± 28; lateral wall=16.2 ± 8.9 versus 31.3 ± 28.9. Similar results were obtained in short-axis view. The perceived filtered image quality indicated decreased noise (VGCAUC=0.96) and artifacts (0.65), improved natural appearance (0.59), cardiac contour sharpness (0.74), and diagnostic acceptability (0.78). The inter-observer variability was excellent (ICC=0.79). All results were statistically significant (P < 0.05). Conclusion: Similarity filtering after DLR improves image quality, possibly enabling dose reduction in dynamic CTP imaging in patient with suspected chronic coronary syndrome. [ABSTRACT FROM AUTHOR]