The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
With graphene emerging as one of the promising materials in exploring novel and reconfigurable electromagnetic devices, in this paper, we summarize and discuss the electromagnetic property of graphene in different frequencies, as well as introduced two kinds of, namely, surface-wave and spatial-wave based electromagnetic devices base on graphene. Simultaneously, typical mechanisms for designing these...
A low-profile wideband unidirectional dipole antenna with U and L-shaped slots loaded is proposed. A prototype with a thickness of 0.175λ was fabricated and measured. The proposed antenna achieves a wide impedance bandwidth of 57% (S11≤ −10 dB) from the frequency of 1.56 to 2.79 GHz. The cross polarization is less than −21 dB over the operating bandwidth. The antenna has an average gain of 8.6 dBi...
This paper proposes a hybrid method for electromagnetic interference (EMI) analysis of braid cable-interconnect network. In this method, the full-wave finite-difference time-domain method (FDTD) and transmission line equation are combined to predict the transient responses of cable-interconnect networks. Transfer impedance model is introduced as connection conditions so that the external field can...
This paper focuses on GNSS and Inertial Navigation System (INS) integration system based on the loosely coupled (LC) and tightly coupled (TC) schemes. This paper describes the system architechture of two systems and presents the mathematical derivation. In order to evaluate the system performance of the two schemes, a real field experiment was carried in the campus of Beijing Jiaotong University....
To ensure the reliability of insulation systems of Type-II inverter-fed motors driven by power electronics, endurance tests should be performed at sinusoidal or repetitive impulsive voltage higher than the partial discharge inception voltage (PDIV) on insulation systems/models according to the standards released by the International Electrotechnical Commission (IEC). When repetitive impulsive voltages...
Multibaseline phase unwrapping (PU) is a critical processing procedure of multibaseline synthetic aperture radar interferometry (InSAR). The presence of phase noise makes Chinese remainder theorem (CRT) method not robust enough and inapplicable in practical cases. In this letter, a method based on a closed-form robust Chinese remainder theorem (CFRCRT) is presented to improve the noise robustness...
Conical bearing is one kind of radial-thrust hybrid bearing, which can carry radial and axial load at the same time. A hydrodynamic lubricated conical sliding bearing was designed and computational methods were used to analyze the lubrication and load carrying performance. The methodology employed computational fluid dynamics (CFD), based on the Navier-Stokes equation and a fluid-structure interaction...
Intelligent video and image analysis technology has been paid much attention recently. But how to effectively evaluate the performance of intelligent video and image analysis methods remains a meaningful and challenging task, which involves many aspects, such as constructing reasonable datasets, developing efficient evaluation tools, designing effective evaluation metrics. We focus on the area of...
In the recent years, the roadside safety accidents happen frequently in our national mountainous area, therefore, determining the roadside safety grades scientifically and reasonably is imperative for the prevention of more roadside accidents in the mountainous area. To qualitatively evaluate the roadside safety grade of the highways in the mountainous area, this paper adopts the Friedman-Tukey projection...
Big data plays an increasingly important role in aircraft integrated health management. This paper introduces the aircraft health management cloud platform, fault feature extraction methods based on deep learning and fault rules network construction, optimization and division.
We experimentally demonstrate a feedback-assisted 1.08 Gb/s orbital angular momentum (OAM)-based underwater-to-air wireless optical link with a floating mirror for beam steering. The experimental results show favorable performance of the proposed feedback scheme in the present of the change of water level.
We experimentally demonstrate visible-light co ding/de co ding utilizing hexadecimal vector beam array for parallel communication link. The hexadecimal base mode is investigated and 128-ary is also available. We present vector beam array carrying 4×6/6×8/12×16 hexadecimal numbers and error-free data stream transmission performance is also demonstrated.
The problem of robust registration of 3D point sets disturbed by noise for free-form surface inspection is considered. In this research, M-estimation methods are used to eliminate the effects of outliers, and a robust extension of tangent-squared distance minimization (TDM) using M-estimation is proposed. The proposed algorithm is compared with standard TDM method, iterative closest point (ICP) method...
In order to handle positions and orientations of tool with a unified manner in 5-axis NC machining, a tool path planning method based on double quaternion was proposed. With the identity of cutter points and the points in double quaternion space, the mapping from position and orientation points in 3D space to elements of double quaternion space is constructed. The interpolation problem of position...
In NC machining of free-form surfaces, low efficiency, unstable machining process and poor quality of the finishing surface occur frequently for the usage of numerous micro segment trajectories. To address these challenges, a B-spline smooth compression (BSC) algorithm of consecutive micro segment trajectories (CMSTs) is proposed. In this algorithm, CMSTs are first extracted according to geometric...
A new data prediction method for electrocardiogram (ECG) signals is proposed in this paper, which combines error back propagation neural network (BPNN) and variational mode decomposition (VMD) technology. The proposed method involves three parts. First, with VMD applied, the ECG signal which contains baseline wander (BW) noise is decomposed into a set of modes. Second, by analyzing the center frequency...
To guarantee the correctness of workflow execution, it is essential to analyze the structural and artifact integrity of workflows. The current best approach of artifact workflow anomaly detection is O(|E|) for structured workflows, however, each of the anomalies returned in the approach contains (artifact, operator) at each workflow node. In this paper, we present an innovative methodology which contains...
The performance analysis of TWOTFT with the two terminal equipments at the two remotes sites has been implemented and one way time transfer through optical fiber has been designed and the performance evaluation, demonstration, and verification experiments in short distance have been realized and its uncertainty has been evaluated as roughly 2.1 ns.
The establishment of flight control system parameters modeling and fault simulation is the basis of fault diagnosis. In this paper, the flight control system simulation model is established by MATLAB / SIMULINK. We describe the modules and implementation methods of the flight control system parameters modeling in detail. In addition, the simulation of the failure mode and realization is introduced...
We propose and experimentally demonstrate a compact integrated silicon photonic comb filter based on two cascaded Sagnac-loop mirrors. By using thermal tuning with three micro-heaters, the center wavelength can be tuned over several FSRs and the 3-dB bandwidth can be tuned to 2.5 GHz.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.