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In order to solve the problems of power transformer such as the fault can be reflected by different characteristic signal from different side and complexity of fault reason and phenomenon, a synthetic diagnosis method using multi-neural network and evidence theory for transformer fault diagnosis is presented. Various kinds of data are dealt by using neural network's excellent abilities of learning,...
Technological advances in digitization with a variety of image manipulation techniques enable the creation of printed documents illegally. Correspondingly, many researchers conduct studies in determining whether the document printed counterfeit or original. This study examines the several statistical feature sets from Gray Level Co-occurrence Matrix (GLCM), Discrete Wavelet Transform (DWT), Spatial...
In order to solve the problem that the existing parallel manipulator is expensive, complicated design and complicated control, this paper designs a three-degree-of-freedom parallel manipulator with cam-driven single power input. The manipulator is cheap and widely used. And then its kinematics research. The freedom degree analysis of the manipulator is completed, and the kinematics is obtained. And...
Cell-free massive multiple-input multiple-output (MIMO), with a large number of distributed access points (APs) that jointly serve the user equipments (UEs), is a promising network architecture for future wireless communications. To reduce the cost and power consumption of such systems, it is important to utilize low-quality transceiver hardware at the APs. However, the impact of hardware impairments...
Strong optical injection into a distributed feedback (DFB) semiconductor is a method to realize a single bandpass microwave photonic filter (MPF). But the out of band suppression ratio (OSSR) is limited by the four wave mixing (FWM) effect, and the 3 dB bandwidth is too large for microwave signals. To improve the OSSR and narrow the 3 dB bandwidth of the MPF, a novel single bandpss MPF based on weak...
A photonic microwave down-conversion scheme using period-one dynamics of semiconductor lasers is proposed. Microwave down-conversion from 35 GHz to 5 GHz with a 19-dB conversion efficiency is experimentally demonstrated for the proof of concept.
This paper describes the effect of the condition evaluation of transmission line Cand the methods of condition evaluation mainly used in current. With a 500kV line as example, shows the process of condition evaluation of the transmission line. This paper also present the problems should be considered in the condition evaluation process. Aiming at the method of transmission line condition evaluation...
A novel 3D image-based indoor localization system integrated with an obstacle removal component is proposed. In contrast with existing state-of-the-art localization techniques focusing on static outdoor or indoor environments, the adverse effects generated by moving obstacles, which are very common in busy indoor spaces, is considered in our work. In particular, this problem is converted into a separation...
In order to improve the coordinated tracking control performance for the speed and tension system of reversible cold strip rolling mill, a backstepping control strategy is proposed based on command filter in this paper. Controller for each of the speed and tension subsystems is designed based on backstepping respectively, meanwhile the command filters are adopted to generate the virtual control inputs...
The visual analysis efficiency also depends on the human-computer interactions, to manipulate and inspect the volume data. This research aims to develop an interactive visualization system using a head-mounted display to analyze three-dimensional volume data, and hands-motions sensor to realize the interactive operations.
In order to reap the full scale of benefits of millimeter wave (mmWave) massive multiple-input multiple-output (MIMO) systems, the design of antenna arrays at the transmitter or receiver becomes more critical due to the propagation characteristic at mm-frequencies. In this paper, we investigate the steering vector and array factor by considering three types of planar antenna arrays, namely uniform...
For the first time, a period-one (P1) nonlinear dynamic modulated MMW OFDM signal is employed to mobile fronthaul uplink. A proof-of-concept experimental demonstrations show successfully retrieved signals after 1.5-m wireless and 25-km SMF transmissions.
Modern power grid has already become one of the pillar industry of the national economy. The safety and steady operation of power grid is closely related to the development of all walks of life, national economy guarantee the fundamental interests of people. So it is significant to guarantee the safety of grid in production, operation, and the electric power supply. In this paper, connecting with...
This paper presents a new OLTC (On-load tap-changing), which can effectively solve the arcs and improve the operating speed. By using the magnetic latching relay instead of the switch, eliminating the complicated mechanical driving mechanism to shorten the voltage regulating time, reduce the failure rate and the cost; Based on the new OLTC the paper studies the automatic regulating, with a Single-Chip...
In order to improve fault recovery characteristic of high-voltage direct current transmission system(HVDC), this paper proposes voltage dependent current order limiter(VDCOL), optimizing arc extinguishing angle controlling and adopting SVC reactive power compensator and so on to improve fault recovery feature after analyzing the main factors influencing fault recovery characteristic. This paper makes...
A tunable dual-mode operation with three-section distributed Bragg reflector (DBR) laser is proposed for compact and low-cost microwave generation. Stable dual-mode operation with 7 nm tuning range is demonstrated.
The purpose of us was investigating the optimal fractional anisotropy (FA) value and apparent diffusion coefficient (ADC) value in the post-process of diffusion tensor tractography (DTT) of prostate. Twenty volunteers without diseases of prostate were included in our clinical trial. Conventional sequences and Diffusion Tensor Imaging (DTI) were scanned in GE Signa HDxt 3.0T Magnetic Resonance Imaging...
In this paper, an online fault diagnosis method of wind turbine blades that is based on SVM (support vector machines) is proposed. First, it uses normalized real-time data of temperature, humidity, brightness and brightness of wind turbine blades to construct feature vectors. Then based on SVM, online fault diagnosis of wind turbine blades can be implemented. Three type of faults which are skin cracking,...
A CMOS bandgap reference using chopping technique for OPAMP offset cancelling is presented in this paper. The OPAMP used in bandgap was intended to improve the precision of the bandgap, but this aim is in some degree reduced by the input referred offset and 1/f noise of the introduced OPAMP. Thus, an effective architecture which contains three pairs of chopping cells is designed to overcome the issue...
Pentacene organic thin-film transistor (OTFT) using Pd as gate electrode is proposed, with high-k LaZrO as gate dielectric. The Pd film is prepared by e-beam evaporation and then the LaZrO film is deposited by reactive sputtering in Ar/O2 ambience followed by an annealing in N2 at 400 °C. The OTFT achieves an obvious increase in carrier mobility (to 1.02 cm2/V·s), as compared with its counterpart...
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