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A microring-Bragg grating based coupling resonant system is experimentally demonstrated to generate switchable EIT-like and Fano transmissions for the first time. The resonance state is dependent on the relation between coupling coefficient and round-trip-intensity-attenuation.
Under the three-phase unbalanced grid condition, the commonly used controller design methods of three-phase voltage source rectifiers (VSR) are based on the instantaneous power model and the current and voltage double-closed loop control structure. The inner current loop proportional integral (PI) controllers are designed for the positive- and negative-sequence current components, separately, therefore,...
A new germanium-on-silicon nitride platform is fabricated and tested for mld-lR sensing applications. Waveguides with low bending loss are demonstrated allowing one to design compact on-chip sensors. Spiral waveguide sensors have been studied for potential drug detection and food processing applications.
In order to adapt to the complicated and changeable topography environment features of the seabed, a composite wheeled submarine vehicle with both passive and passive hybrid obstacle negotiation model is proposed in this paper. Taking the composite wheeled seabed mining vehicle as the object of study, the features of seabed unstructured terrain environment are extracted, and the process of adaptive...
This paper proposes a motion trajectory control method of underground intelligent scraper based on particle swarm optimization. The simulation model of whole system was established in simulink according to autonomous navigation bivariate PID control algorithm and scraper motion control model. The process of particle swarm optimization was designed based on MATLAB platform. The parameter optimization...
In this paper, the compressive sensing (CS) is introduced into fast multipole method (FMM) for the purpose of reducing the angle sampling rate in solving multi-static scattering problems. The scattered fields induced by all excitations on one scattering angles are viewed as the proceeded signal, which is sparsely sampled by CS. Then the Huygens principle is introduced to convert the sparse sampling...
Under a radar-based mini-size unmanned aerial vehicle (mini-UAV) classification scenario, the mini-UAV physical parameters play an important role. The parameters can be retrieved from radar blade flashes induced by rotor blades. In this work, we propose a novel method for enhancing the distinctive-ness between blade flashes so that the physical parameters can be better estimated. Essentially, the...
A hypersonic vehicle is covered by an inhomogeneous and time-varying plasma sheath when it reenters the Earth's atmosphere. To investigate the effects of scattering in the plasma sheath on electromagnetic (EM) wave, the JE convolution-finite-difference time-domain algorithm is applied to three-dimensional time and spatially inhomogeneous plasma. The radar cross-section (RCS) of plasma sheath is analyzed...
The commonly used method for grading spasticity in clinical applications is Modified Ashworth Scale (MAS). The MAS-based method depends on the subjective evaluations and the experience of physicians, which may lead to imprecise and inconsistent evaluations. In this study, we propose a novel index (A-ApA, which was calculated with the root mean square (RMS) of agonist muscle activity by the mean between...
A dual-band optical filter based on a single microring resonator embedded with nanoholes is theoretically and experimentally demonstrated for the first time. A numerical model based on transfer matrix method is utilized to simulate the performance of this device. The coupling between the microring resonator and the Fabry-Pérot resonator formed by nanoholes gives rise to the dual-band optical filtering...
The unbalanced grid condition is one of common fault in the power system, the performance of electronic equipment will reduce when the controller designer without considering the unbalanced grid input. The traditional controller design methods of three-phase pulse width modulation (PWM) converter, are based on the instantaneous power model and the double-closed loops proportional integral (PI) controller,...
The successful fabrication of MIR Ge-on-Si waveguides written by both the high-resolution electron beam lithography (EBL) approach, as well as the wafer scale, high throughput approach using 365 nm i-line stepper lithography is reported. A low propagation loss of ∼2.7 dB/cm at a wavelength of 3.8 μm is shown for Ge-on-Si waveguides patterned using the i-line stepper. The waveguide etching technique,...
The Alzheimer's Disease (AD) has become a major threat of human health with its incidence rate ascending year by year. Early diagnosis of AD is very important for AD patients to keep life quality. The resting-state fMRI (rs-fMRI) which precisely reflects the brain changes on the resting state of individuals provides a quantitative approach, which has been introduced to distinguish AD patients from...
In this paper, a differentially-fed charge pumping rectifier design is presented with an enhanced efficiency for ambient RF energy harvesting. Due to the differential signals induced by a delicately designed rat-race coupler, circuit topology of the modified Greinacher rectifier is simplified with an enhanced RF-to-dc power conversion efficiency (PCE) over low power ranges. Meanwhile, high output...
Grating coupler based on 220 nm Si-on-insulator (SOI) substrate was designed and optimized for operation at 2 μm wavelength targeting telecommunication application. Decent coupling efficiency of around 18% is achieved, which is consistent with the simulation results and can be employed in 2 μτη-based photonic integrated circuit.
Various electromagnetic (EM) structures become more complex and often have increasing degrees of design freedom. Classical optimization methods require numerous simulation trials of different parameter combinations, which leads to a low design efficiency. To address this problem, an efficient EM structure optimization algorithm which combines differential evolution (DE) with machine learning technology...
This paper presents the design of a D-band (110–170 GHz) iris bandpass filter (BPF) for 3-D printing fabrication. Taking the advantage of the 3-D Mask Printing technology, the dimensional tolerance and surface roughness are much improved compared with the Selective Laser Melting (SLM) printed filter. The 3-D Mask Printed filter has a passband 144–146 GHz (|S11|<−18 dB) with in-band insertion loss...
In this research, we propose a novel MEMS sensor based on Laterally Movable Gate Array Field Effect Transistor (LMGAFET) for the measurement of nN force. By designing an array structure and adopting reasonable parameters and utilizing modified MOS3 model, the sensor's proved to have high sensitivity of 0.107 mA/nN, low cross-axis sensitivity and excellent linearity. Besides, a modified MOS3 model...
A novel piezoresistive sensitive structure for micromachined high-pressure sensors is proposed. This structure employs several small cavities in a silicon bulk. When high pressure applied on all faces of the bulk, stress emerges between two cavities. The calculation for the variation of the resistance caused by stress in three-dimensional (3D) structure was discussed. According to 3D piezoresistive...
Online learning resources growth speed is in geometric series with the rapid development of computer and communication technology. Users in distance learning and training process encounter the problems of information loss and resource overload, the main reason is that the distance learning system can't effectively understanding of teaching resources semantic information, different structure of teaching...
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