Microsyst Nanoeng
November 2024
Limited to the direct modulation on the surface acoustic wave (SAW) by the rotation, the conventional SAW gyroscopes incur weak Coriolis effects and gyroscopic effects. In this paper, we innovatively utilize a phononic metamaterial (PM) operated at whispering-gallery modes (WGMs) as the vehicle for the Coriolis effect rather than SAW itself. The gyroscopic effects of this PM are investigated, and a new SAW gyroscope is subsequently proposed based on the slow SAW in PM.
View Article and Find Full Text PDFNitrogen-vacancy (NV) centers in diamond are promising quantum sensors, where microwave antennas play a crucial role in manipulating the spin states accurately. Conventional microwave antennas often struggle to balance radiation efficiency and bandwidth. To address this challenge, we design a planar double-turn spiral antenna (PDTSA), based on the ring microstrip antenna (RMA).
View Article and Find Full Text PDFWhen humans consume seafood contaminated by lipophilic polyether phycotoxins, such as azaspiracids (AZAs), the toxins are mainly leached and absorbed in the small intestine, potentially causing intestinal damage. In this study, human intestinal epithelial Caco-2 cells were used to investigate the adverse effects of azaspiracid-2 (AZA-2) on human intestinal epithelial cells. Cell viability, apoptosis, oxidative damage and mitochondrial ultrastructure were investigated, and ribonucleic acid sequence (RNA-seq) analysis was applied to explore the potential mechanisms of AZA-2 toxicity to Caco-2 cells.
View Article and Find Full Text PDFIntelligent signal processing in unmanned stores enhances operational efficiency, notably through automated SKUs (Stock Keeping Units) recognition, which expedites customer checkout. Distinguishing itself from generic detection algorithms, the retail product detection algorithm addresses challenges like densely arranged items, varying scales, large quantities, and product similarities. To mitigate these challenges, firstly we propose a novel boundary regression neural network architecture, which enhances the detection of bounding box in dense arrangement, minimizing computational costs and parameter sizes.
View Article and Find Full Text PDFMicromachines (Basel)
February 2023
There are various errors in practical applications of micromachined silicon resonant accelerometers (MSRA), among which the composition of random errors is complex and uncertain. In order to improve the output accuracy of MSRA, this paper proposes an MSRA random error suppression method based on an improved grey wolf and particle swarm optimized extreme learning machine (IGWPSO-ELM). A modified wavelet threshold function is firstly used to separate the white noise from the useful signal.
View Article and Find Full Text PDFNanomaterials (Basel)
December 2022
Carbon nanotubes (CNTs) show significant advantages in the development of cold cathode X-ray tubes due to their excellent field emission performance; however, there are still some problems, such as short lifetime and the low emission current of large-area CNTs. In this paper, a front-grid carbon nanotube array model was established, and the electric field intensity near the tip of the CNTs' electric field enhancement factor was analytically calculated. A simulation model of a CNT three-dimensional field emission electron gun was established by using computer simulation technology (CST).
View Article and Find Full Text PDFMicromachines (Basel)
September 2022
The nitrogen-vacancy (NV) center of the diamond has attracted widespread attention because of its high sensitivity in quantum precision measurement. The phonon piezoelectric device of the NV center is designed on the basis of the phonon-coupled regulation mechanism. The propagation characteristics and acoustic wave excitation modes of the phonon piezoelectric device are analyzed.
View Article and Find Full Text PDFThe output of the micromachined silicon resonant accelerometer (MSRA) is prone to drift in a temperature-changing environment. Therefore, it is crucial to adopt an appropriate suppression method for temperature error to improve the performance of the accelerometer. In this study, an improved firefly algorithm-backpropagation (IFA-BP) neural network is proposed in order to realize temperature compensation.
View Article and Find Full Text PDFComput Math Methods Med
June 2022
An improved channel attention mechanism Inception-LSTM human motion recognition algorithm for inertial sensor signals is proposed to address the problems of high cost, many blind areas, and susceptibility to environmental effects in traditional video image-oriented human motion recognition algorithms. The proposed algorithm takes the inertial sensor signal as input, first extracts the spatial features of the sensor signal into the feature vector graph from multiple scales using the Inception parallel convolution structure, then uses the improved ECA (Efficient Channel Attention) channel attention module to extract the critical details of the feature vector graph of the sensor data, and finally uses the LSTM network to further extract the temporal features of the inertial sensor signals to achieve the classification and recognition of human motion posture. The experiment results demonstrate that 95.
View Article and Find Full Text PDFThis study designed an in-plane resonant micro-accelerometer based on electrostatic stiffness. The accelerometer adopts a one-piece proof mass structure; two double-folded beam resonators are symmetrically distributed inside the proof mass, and only one displacement is introduced under the action of acceleration, which reduces the influence of processing errors on the performance of the accelerometer. The two resonators form a differential structure that can diminish the impact of common-mode errors.
View Article and Find Full Text PDFMicromachines (Basel)
November 2021
Surface acoustic wave gyroscopes (SAWGs), as a kind of all-solid-state micro-electro-mechanical system (MEMS) gyroscopes, can work normally under extremely high-impact environmental conditions. Among the current SAWGs, amplitude-modulated gyroscopes (AMGs) are all based on the same gyro effect, which was proved weak, and their sensitivity and intensity of the output are both lower than frequency-modulated gyroscopes (FMGs). However, because FMGs need to process a series of frequency signals, their signal processing and circuits are far less straightforward and simple than AMGs.
View Article and Find Full Text PDFThis paper presents the characterization of the modal frequencies and the modal orientation of the axisymmetric resonators in Coriolis vibratory gyroscopes based on the approaches of the frequency sweep and the ring down. The modal frequencies and the orientation of the stiffness axis are the key parameters for the mechanical correction of the stiffness imperfections. The frequency sweep method utilizes the zero and the poles in the magnitude-frequency responses of the two-dimensional transfer function to extract the modal orientation information within the frequency domain.
View Article and Find Full Text PDFA biomimetic study on the auditory localization mechanism of was performed to improve the localization ability of small acoustic systems. We also present a microscale implementation of an acoustic localization device inspired by the auditory organ of the parasitic . The device consists of a pair of circular membranes coupled together with an elastic beam.
View Article and Find Full Text PDFThe output model of a rotating accelerometer gravity gradiometer (RAGG) established by the inertial dynamics method cannot reflect the change of signal frequency, and calibration sensitivity and self-gradient compensation effect for the RAGG is a very important stage in the development process that cannot be omitted. In this study, a model based on the outputs of accelerometers on the disc of RGAA is established to calculate the gravity gradient corresponding to the distance, through the study of the RAGG output influenced by a surrounding mass in the frequency domain. Taking particle, sphere, and cuboid as examples, the input-output models of gravity gradiometer are established based on the center gradient and four accelerometers, respectively.
View Article and Find Full Text PDFIn this study, we investigated the effect of high-molecular-weight glutenin subunits (HMW-GSs) on gluten quality and glutenin synthesis based on the cytological, physicochemical, and transcriptional levels using Xinong1718 and its three near-isogenic lines (NILs). Cytological observations showed that the endosperm of Glu-1Bh with Bx14+By15 accumulated more abundant and larger protein bodies at 10 and 16 days after anthesis than the other NILs. Glu-1Bh exhibited higher nitrogen metabolism enzyme gene expression and activity levels.
View Article and Find Full Text PDFWheat gluten properties can be improved by the application of nitrogen. This study investigates the effects of nitrogen application in the booting stage on glutenin polymerization during grain-filling and structural-thermal properties of gluten based on the high-molecular-weight glutenin subunits (HMW-GSs) using near-isogenic lines ( and ). The nitrogen rate experiment included rates of 0, 60, 90, and 120 kg N ha applied with three replicates.
View Article and Find Full Text PDFTo further understand the gluten-starch interactions in dough, this study investigated the effects of exogenous starch on the structural-thermal properties of gluten via reconstituting Xinong 836 starch with gluten from near-isogenic lines HMW-D1a (Dy12) and HMW-D1p (Dx2 + Dy12) according to the following proportions (gluten/starch): 9/91 (G09), 12/88 (G12), 15/85 (G15), and two controls, where G00 and G01 represent the original and self-reconstituted flours, respectively. Adding exogenous starch significantly improved the dough strength for the reconstituted flours containing gluten from HMW-D1a and HMW-D1p, especially those with HMW-D1a. When the ratios of gluten to starch were 15/85 and 12/88 in the HMW-D1a and HMW-D1p reconstituted flours, respectively, the concentrations of free sulfhydryl groups were minimized in the flour, and thus more glutenin polymers were formed.
View Article and Find Full Text PDFAbsence of high-molecular-weight glutenin subunit (HMW-GS) Dx2 weakens the gluten quality, but it is unclear how the absence of Dx2 has these effects. Thus, we investigated the gluten quality in terms of cytological, physicochemical, and transcriptional characteristics using two near-isogenic lines with Dx2 absent or present at locus. Cytological observations showed that absence of Dx2 delayed and decreased the accumulation of protein bodies (PBs), where fewer and smaller PBs formed in the endosperm.
View Article and Find Full Text PDFIn this paper, we present a new design for a micro-opto-electro-mechanical (MOEMS) gyroscope based on a whispering-gallery mode (WGM) microdisk resonator and MEMS resonator. The mechanical characteristics, frequency split, and quality factor (Q) of the MEMS resonator; the optical characteristics, Q value, and coupling regimes of the WGM resonator; and the coupling between the two resonators were analyzed. Its operation principle-the transformation process from angular velocity to the resonance wavelength of the WGM resonator-is presented at same time.
View Article and Find Full Text PDFMicromachines (Basel)
June 2019
Coriolis vibratory gyroscopes (CVGs) with circular micro-resonators, such as hemispherical, ring, and disk resonators, exhibit excellent performances and have extraordinary potential. This paper discusses a generalized lumped mass model for both 3D and planar circular micro-resonators, establishing the relationship between the modal effective mass, the modal equivalent force, and the point displacement of the resonator. The point displacement description of a continuous circular resonator's motion is defined from the view of capacitance measurement.
View Article and Find Full Text PDFMicromachines (Basel)
April 2019
A micro optoelectromechanical system (MOEMS) resonator gyroscope based on a waveguide micro-ring resonator was proposed. This sensor was operated by measuring the shift of the transmission spectrum. Modal analysis was carried out for the disc sensitive structure of the MOEMS resonator gyroscope (MOEMS-RG).
View Article and Find Full Text PDFSensors (Basel)
November 2013
The micromechanical silicon resonant accelerometer has attracted considerable attention in the research and development of high-precision MEMS accelerometers because of its output of quasi-digital signals, high sensitivity, high resolution, wide dynamic range, anti-interference capacity and good stability. Because of the mismatching thermal expansion coefficients of silicon and glass, the micromechanical silicon resonant accelerometer based on the Silicon on Glass (SOG) technique is deeply affected by the temperature during the fabrication, packaging and use processes. The thermal stress caused by temperature changes directly affects the frequency output of the accelerometer.
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