This article reviews the investigation of the mode-localized microelectromechanical system (MEMS) coupled resonant sensors. This class of a sensor features a new approach in the sensing method (i.e. sensing shifts in the eigenstates/amplitude ratio (AR) instead of a frequency shift) in resonant devices. The key performance metrics and progress in terms of sensitivity, noise optimization, resolution

Condition monitoring is a significant requirement for ensuring safe and reliable working of machining processes and rotary components. Recent developments in digital signal processing techniques along with emergence of miniature sensors and high-speed data acquisition devices furnish a peculiar opportunity for the development and implementation of effective, in-situ, non-intrusive condition monitoring

Minimally invasive robotic interventions have highlighted the need to develop efficient techniques to measure forces applied to the soft tissues. Since the last decade, many scholars have focused on micro-scale and macro-scale robotic manipulations. Early articles used the model of soft tissue mathematically and tracked the displacement of the contour of the object in the vision system to provide the

As the CMOS-based ion-sensitive field-effect transistor (ISFET) is scaling down to achieve a compact sensing array with high spatial resolution, reduction of sensing layer capacitance attenuates capacitive coupling efficiency of environmental input signals and decreases sensitivity performance. To address this issue, a concept of three-dimensional (3D) sensing structure is proposed and examined in

In this study, silicon nanowire (SiNW) FET-based and SiNW tunnel FET (TFET)-based biosensors are co-integrated with CMOS circuits by using top-down approached and CMOS-compatible back-end process simultaneously. The possibility of multiplexed sensing is verified with the fabricated FET and TFET biosensors. For multiplexed-sensing, two separate sensing materials which react with two distinct bio-targets

Label-free monitoring of biomaterials has become spotlight topic for the advanced nano-biosensing fields. In this regard, a non-destructive doping-less tunneling carbon nanotube field effect transistor (DL-TCNTFET) -based biosensor using the charge plasma concept is introduced. In doping-less structures, source and drain are created using the concept of charge plasma and by selecting appropriate work

Biosensor is a detection device composed of a biologically active unit and a signal converter. In a eusocial honeybee colony, worker bees have also evolved a sophisticated olfactory system to specifically sense the queen pheromone components. So far, it is not clear whether it is possible to design a biosensor to detect the queen pheromone in vitro by using worker bees’ olfactory system. In this study

Wearable biosensors are considered to be a promising technology that revolutionizes conventional health monitoring methods as it is able to provide precautions when potential health problem is detected. However, the current fatigue-monitoring methods are still using either invasive blood tests or bulky inconvenient devices. Herein, we present a new skin patch sensor based on porous Ultra-High-Molecular-Weight

Monitoring the gases released during breathing or via the skin has gained significance towards diagnosing diseases. In this study, a sensor chip capable of detecting nonanal gas, which is known to be a marker of lung cancer, was developed. The gas detection agent used was vanillin, which underwent aldol condensation with nonanal in the presence of a basic catalyst, resulting in the formation of an

Over the past several decades, metal oxide based gas sensors are widely used for hydrogen gas sensing applications. However, their poor sensitivity and very high value of operating temperature (> 300 °C) pose a severe threat over hydrogen detection due to its highly flammable nature. In recent years, a few strategies have been explored by the researchers to address these formidable challenges faced

A novel humidity sensor based on polymer-salt complexes was developed in this research. Poly(ethylene glycol) (PEG) segmented poly(ether ether ketone) copolymers (PEEK-co-PEG) has been successfully synthesized via condensation polymerization and the structure of this copolymer was confirmed by 1 H NMR. Humidity sensors based on SPEEK/PEEK-co-PEG composites were prepared, and then humidity sensitive

A 2-D analytical model of a dielectric modulated trench double gate junctionless FET (DM-TDGJLFET) is developed for label-free detection of biomolecules. The channel potential is obtained by solving the 2-D Poisson’s equation using the parabolic approximation with appropriate boundary conditions. The drain current and threshold voltage are obtained from the minimum channel potential. The proposed DM-TDGJLFET

In medical applications, sensing forces along surgical tools is of high importance in order to avoid collateral damage of tissue and surrounding structures. However, the space available in their central lumen limits the routing of wired sensors that are widely available today, and thus their integration into such tools. In this paper, we present a new wireless force sensor based on wave backscattering

Ensuring both feasibility and reliability when measuring forces and torques in legged robots is challenging. Different transducer technologies and structural designs can be used to develop force/torque sensors with multiple measurement axes, high accuracy, and durability. Among the said technologies, strain gauges are frequently used, due to their high accuracy and compatibility with various materials

This paper presents a high-sensitivity micromachined resonant differential pressure sensor based on bulk silicon. The sensor includes a sensing unit made of a SOI wafer, which is vacuum packaged by a glass-on-silicon (GOS) wafer. More specifically, two resonators located in the SOI device layer were coupled to the GOS glass layer and deployed on the central and side areas of the pressure-sensitive

Acoustic hologram enable the capability in the acoustic pattern control and drive many applications of ultrasound. However, hologram has not been applied to ultrasound imaging because the medical application of acoustic holograms is limited owing to the sound reflection and scattering at the acoustic holographic surface and its internal attenuation. In this study, we propose an acoustic holographic

Pencil (graphite) on paper (PoP) electronics has gained significant attention due to its low cost and versatility in developing customizable disposable electronics. Despite the convenience of the PoP methodology in device fabrication its application in developing electronics is limited due to the absence of a bandgap in graphite. The present work is the first demonstration of the direct writing of

Modal actuation and sensing are implemented on a microfabricated AFM cantilever with a two-layer piezoelectric stack transducer. The top transducer is shaped as the second derivative of the first mode shape. The bottom transducer is uniformly distributed along the cantilever length. The purpose of this work is to demonstrate that modal actuation and sensing can be used to eliminate other resonances

The multifunctional application of carbon fiber reinforced polymer composites (CFRP) can be affected by the anisotropic electrical conductivity of the carbon fiber because it differs in the longitudinal and the transverse direction of the fiber. In our article, we measured the transverse resistivity of the reinforcing carbon fiber bundle in different conditions: when the fibers were dry, when they

In this paper, an absolute time-grating displacement sensor with high accuracy and high resolution is proposed, where primary, secondary, and tertiary stage capacitor arrays with ${M}$ , ${N}$ , and ${N}$ –1 measurement periods, respectively, are combined by a multi-stage composite method that applies the four orthogonal traveling wave signals output by the primary-stage as the excitation signals of

Force measurement on steel wire rope (SWR) is significant to ensure the safety of people and property. Previous methods propose the electro-magnetic sensor, which measures the force applied on the SWR non-invasively and does not damage the structure of the SWR. Based on the magneto-elastic effect and integration of induction voltage as the indicator, electro-magnetic sensors perform well in many situations

This paper describes a hybrid mass sensing system comprising a QCM (quartz crystal microbalance) mass sensor operating under atmospheric pressure and a 3-DOF mode localized coupled resonator operating in vacuum. Nanoparticles as consecutive mass perturbations are added onto the QCM, the output signals with respect to the amount of mass change are then being manipulated to generate electrostatic forces

Various types of interference signals are available in the working environment of passive wireless surface acoustic wave (SAW) sensors. Among these kinds of interference, co-channel interference is difficult to suppress. To solve this problem, a SAW sensor anti-interference technology was proposed to improve the reliability of the SAW sensor. Wavelet denoising method was used to denoise SAW resonator

The quartz crystal microbalance (QCM) is an ultra-sensitive measuring device and has been commonly used in many specific applications. The mass sensitivity distribution curve of m-m type QCM (QCM with symmetrical electrode) is a Gaussian distribution. However, achieving highly accurate and repeatable measurements requires the uniform distribution of mass sensitivity. To improve the uniformity of QCM

In this study, microwave (9.2 GHz) magnetic field radiation patterns of a horn antenna in the near-field (10 cm) and of a patch antenna in the near-field (3 mm, 2 cm) and far-field (10 cm) are measured using a Cs atomic sensor with < 2 mm size, for the first time to the best of our knowledge. Radiation patterns measured using the atomic sensor are compared to radiation patterns measured in an anechoic

The electromagnetic flow meter (EMF) is one of the most suitable flowmeter for slurry measurement. It is an important research point of electromagnetic flowmeter to overcome slurry noise in slurry measurement. The main approach to overcome slurry noise is to modify the excitation method and to improve the signal processing method. The novelty of this paper is the first study on the mechanism of excitation

The fabrication and testing of hierarchical architecture based Zinc Ferrite-Zinc oxide (ZnFe 2 O 4 -ZnO) magnetic semiconductor (MS) sensor, for the detection of Hydrogen (H 2 ) down to 50 parts per million (ppm) at room temperature, are reported in this study. The synthesis of ZnFe2O4-ZnO heterostructure has been carried out using a simple hydrothermal route. The MS sensor shows good sensitivity,

A multimode microcavity sensor based on a self-interference microring resonator is demonstrated experimentally. The proposed multimode sensing method is implemented by recording wide band transmission spectra that consist of multiple resonant modes. It is different from previous dissipative sensing scheme, which aims at measuring the transmission depth changes of a single resonant mode in a microcavity

In this study, the main focus is laid on the design of an optoelectronic converter as a part of the quantum radar to enhance the entanglement between retained and returned modes at high temperatures. The electro-opto-mechanical converter has been widely studied, and the results showed that the operation at high temperature is so crucial to generate and preserve the entanglement between modes. The main

The blackbody radiation can provide light source for the fiber Fabry-Perot sensor system, but the output signal is difficult to demodulate. Because the signal of Fabry-Perot sensor is modulated by spectrum of blackbody radiation and SNR of signal is low. In this paper, the characteristics of the fiber Fabry-Perot sensor signal based on the blackbody light source were investigated. Effect of spectrum

Extraordinary optical transmission (EOT) is generated when light transmits through an array of subwavelength holes on a metallic sheet. Most studies have focused on the EOT effect with ideal cylindrical holes. Subsequently, it has been recognized that imperfection in hole fabrication could alter light-matter interaction. Later, adiabatic taper is reported to promote light nano-focusing effect in the

Gas-liquid slug flow in horizontal pipes occurs frequently in industrial applications and is harmful to the piping systems owing to its intermittent structures. Therefore, it is essential to accurately describe the flow structure and investigate the flow mechanism. A non-intrusive fluorescence imaging method is employed to quantitatively reconstruct the slug bubble in a 15mm ID horizontal pipe in this

Inverse synthetic aperture radar (ISAR) imaging is an important technique for moving target identification and classification. For the space spinning targets, a long-time observation is required to estimate the spinning parameter in the conventional ISAR imaging methods. However, for the advanced multifunctional radar, which is used for multi-target surveillance, a long-time observation for only one

Due to the influence of the complex marine environment, the marine target detection based on statistical theory is difficult to achieve high-performance. Moreover, due to various targets’ motion characteristics, only using a single feature for detection is unreliable. In this paper, from the perspective of feature extraction and classification, marine target and sea clutter are classified by deep learning

An increasing number of micro/nano-components with complex structures have emerged in recent years. Different kinds of feature sizes usually exist in a single component and require the use of instruments with nanometer-level accuracy. The traditional types of equipment cannot meet the current demands because of their lack of function and effectiveness. In this study, a multifunctional probe is designed

Cylindrical waveguides filled with anisotropic metamaterials enable novel wave propagation phenomena. A nanoporous alumina microtube is a manifestation of such an anisotropic waveguide with an effective permittivity tensor ( $\varepsilon _{r} \neq \varepsilon _\phi = \varepsilon _{z}$ ). The metamaterial would be considered to be filled homogeneously or inhomogeneously depending on the variation of

In this study, we present a quantitative evaluation of the accuracy of simultaneous array-radar-based measurements of the displacements caused at two parts of the human body by arterial pulse wave propagation. To establish the feasibility of accurate radar-based noncontact measurement of this pulse wave propagation, we perform experiments with four participants using a 79-GHz millimeter-wave ultra-wideband

This paper presents a sensitive microwave near-field sensor based on utilizing a three-dimensional capacitor within a planar split-ring resonator. The planar resonator is etched in the ground plane of a microstrip line, where the resonator’s length is relatively smaller than the guided wavelength. The sensor was fabricated utilizing PCB technology and used to detect the presence of dielectric fluids

We propose a compact assemble-easy cost-effective vector bending sensor consisting of a short section of single stress-applying fiber (SSAF) spliced between two standard single-mode fibers (SMFs). The SSAF is specially designed by introducing a stress-applying part (SAP) into the cladding to achieve the asymmetrical geometry. Because of the mode field mismatch between the SMF and the SSAF, the cladding

In this paper, we report on the comprehensive study on Molybdenum disulfide (MoS 2 ) nanolayer coated etched Fiber Bragg Grating (eFBG) strain sensor. MoS 2 nanolayer is coated using Physical Vapor Deposition (PVD) of Molybdenum (Mo) on eFBGs followed by sulfurization of the same in an inert atmosphere at 450° C. Such coating technique provides a direct control over the coating thickness of MoS 2

The real-time, continuous, beat-to-beat blood pressure (BP) monitoring is vital in clinical scenarios such as operations theatres, ambulances etc. In the present study, a non-invasive BP monitoring methodology based on Fiber Bragg Grating sensors is reported. The design and development of Fiber Bragg Grating based Pulse Monitoring Device (FBGPM) is demonstrated which is capable of acquiring the radial

Gait analysis is vital from the view of its established capacity as an indicator for neuromuscular disorders. Gait analysis is carried out in order to provide a quantified assessment of human movement which may aid orthopaedic and podiatric fraternity to suggest suitable therapeutic treatment. The proposed study comprises of two wearable non-invasive devices realized using FBG sensors i.e. Knee Angle

In this paper, an interferometric optical fiber perimeter security system based on multi-domain feature fusion and support vector machine (SVM) is reported. To improve the intrusion event classification accuracy and reduce the overall cost, advanced optical fiber sensor technique and data analysis method are synthesized to build the system. For the optical component, the Michelson interferometer sensor

We demonstrate a simple method for fabricating polymer end-capped fiber optic sensors with highly reproducible features. The polymer used for the devices is polydimethylsiloxane (PDMS) deposited on the cleaved end of a standard single-mode fiber forming a fiber-optic Fabry-Pérot interferometer (FFPI). Deposition is done by immersing the fiber tip into pre-cured PDMS at a prescribed velocity set by

The excellent characteristics of nanocellulose fiber-based papers have made them one of the most attractive and innovative materials for the development of electrochemical paper-based analytical devices (ePADs). Here, the authors describe a new ePAD based on cellulose nanofibers (CNs) for the determination of glucose concentration from whole blood samples. Cellulose acetate (CA) nanofibers were prepared

We propose a novel method to measure and analyze depth resolution in near range. Depth resolution is the smallest depth difference that can be detected by a depth camera, which is an important parameter but is hard to be measured accurately. Intuitively, a stair-shaped target is preferred to measure depth resolution but has many limitations. To overcome the difficulties, we use a flat target and move

In industrial processes, early detection of anomalies is crucial for reducing process failures, meeting the quality assurance (QA) requirements, and lowering raw material wastage. Therefore, anomaly detection algorithms should identify an anomaly in a timely manner, and hence, allows immediate corrective actions to be applied. In this context, this paper proposes a low-complexity algorithm for detecting

In Surveillance Wireless Sensor Networks (SWSN), the nodes are distributed at the borders to detect unauthorized intrusions. In such applications, as the nodes are usually equipped with limited batteries and the network area is harsh to be accessible for humans, energy efficiency is considered as one of the main issues in designing the sensor networks. In the last years, Wireless Rechargeable Sensor

There are two main contributions in this article. One is that an extraction means of dominant frequencies is proposed for the first time. The footstep events (FEs) from diverse subjects are analyzed comparatively in frequency domain. Besides the extraction of dominant frequencies containing rich feature information is successfully accomplished after numerous experiments. The other is novel footstep

It is difficult to achieve satisfactory classification results for bearing fault diagnosis methods based on prior knowledge. This paper presents an adaptive convolution neural network based on Nesterov momentum for rolling bearing fault diagnosis. Firstly, the traditional momentum method in the network is replaced by Nesterov momentum. Nesterov momentum can predict the falling position of parameters

Image reconstruction of Electrical Impedance Tomography (EIT) is a highly nonlinear ill-posed inverse problem, which is sensitive to the measurement noise and model errors. An improved Convolutional Neural Network (CNN) method is proposed for the EIT lung imaging. The proposed method is optimized based on the Visual Geometry Group (VGG) model, adding the batch normalization (BN) layer, ELU activation

As more and more oil fields enter the high water-cut stage, it is of great significance to develop low-cost multiphase flow meters (MPFMs) for high water-cut flows. Based on characteristic parameters of the interfacial wave, this article presents a cost-effective method for flowrate measurement of gas-water slug flow in the horizontal pipeline, which has a great potential to be developed as a key technique

This paper proposes a novel 3D action recognition technique that uses time-series information extracted from depth image sequences for use in systems of human daily activity monitoring. To this end, each action is represented as a multi-dimensional time series, where each dimension represents the position variation of one skeleton joint over time. The time series is then mapped onto a vector space

Optimizing the adaptive circuit of piezoelectric sensors is important in accurately measuring blast waves. This study analyzed the impact of the bandpass cut-off frequencies and quality factor of adaptive circuits on shock wave measurements. We proposed a Multi-objective particle swarm optimization based on weighted Pareto-dominance sort (W-MOPSO) for optimizing the multi-objective function of an adaptive

High precision measurement is becoming an imperative requirement in many applications. A novel sub-pixel line-edged angle detection method based on convolutional neural network is proposed in this paper. The line edges of targets are accurately estimated by their geometric slope angles with an edge point located on the line. Specifically, the pixel level line-edged images are first obtained by image

Saliva has emerged as an efficient screening sample for early stage detection of oral cancer (OC) owing to non-invasiveness coupled with high sensitivity and specificity. Although spectroscopic characterization of saliva in oral potentially malignant disorders OPMDs) and OC is extensively studied, its potential as imaging biomarker is sparsely explored. Further, the literature on crystalline pattern

Accurate attitude for wearable devices and smartphones is needed for many applications. The major challenge is to cope with the acceleration resulting from the user or smartphone dynamics. To that end, a two-stage adaptive complementary filter for attitude estimation is proposed. Upon identifying the smartphone location on the user using a deep learning approach, the accelerometers weights in each

Objectives: Identification of cow lameness is important to farmers to improve and manage cattle health and welfare. No validated tools exist for automatic lameness detection. In this research, we aim to early detect the cow lameness by identifying the instantaneous fundamental gait harmonics from low frequency (16Hz) acceleration signals recorded using leg-worn sensors. Methods: A triaxial accelerometer

Deep learning-based algorithms showed promising prospects in the computer vision domain. However, their deployment in real-time systems is challenging due to their computational complexity, high-end hardware prerequisites, and the amount of annotated data for training. This paper proposes an efficient foreground detection (EFDNet) algorithm based on deep spatial features extracted from an RGB input

Annually, numerous cattle die of various diseases, necessitating the need for effective cattle health management. To ensure cattle disease detection at an early stage and identify the health status of cattle, we collected the environment temperature, humidity, illuminance, and infrared images of cattle in an actual-life environment as input parameters to develop an artificial intelligence characterization