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.
A capacitor voltage-balancing control strategy based on switching state redundancies is proposed for the hybrid stacked five-level converter. In order to obtain the balancing properties for flying capacitors, a hybrid model in state-space representation is established by considering the continuous and discrete variables. The proposed balancing strategy can control the flying capacitor voltages to...
This paper proposes a new modular multilevel converter with symmetric bidirectional DC fault blocking capability for high voltage direct current transmission systems. The new modular multilevel converter is composed of novel submodules, which is developed from a three-level T-type converter combined with some clamp circuits. The proposed novel submodule can output three voltage levels with six IGBTs,...
This article investigates a mobile control problem for a class of stochastic distributed parameter systems with moving boundaries by using mobile sensor-actuator networks(MSANs). The network induced randomly missing measurements among the sensors are introduced for their universal existence in sensor networks. The collocated sensor-actuator networks which can travel throughout the spatial domain are...
A temperature demodulation method by using compensation of fiber attenuation and dispersion for distributed temperature sensors (DTS) is proposed and demonstrated in order to improve the DTS measuring speed and accuracy. Firstly, the attenuation coefficients difference between anti-Stokes and Stokes backscattering is modified, which avoids the calibration processing on the entire sensing optical fiber...
In this paper, an algorithm is proposed to estimate thousands of channel parameters in massive multiple-input multiple-output (MIMO) systems with a three-dimensional antenna array, using only one training symbol while assuming no knowledge of path number, noise power, path gain and direction-of-arrival (DOA) statistics. Furthermore, the received data structure is exploited to give a low-complexity...
We present the first demonstration of distributed strain/temperature sensing in side hole fibers (SHFs) based on Brillouin optical time domain analysis systems (BOTDA). The Brillouin frequency shift (BFS) of 10.22 GHz and the Brillouin linewidth of 40 MHz were measured. The temperature and strain coefficients of the Brillouin frequency shift are 1.08 MHz/O and 0.089 MHz/με, respectively. Compared...
In this article, a mobile control scheme is proposed for a class of stochastic distributed parameter systems with time-dependent spatial domains with the aid of a mobile actuating device equipped with a simple output feedback controller. The almost locally distributed state information is assumed to be provided by sensors dotted about the spatial domain where the moving actuating device is able to...
The temperature properties of bismuth active centers (BACs) on Bismuth/Erbium co-Doped Optical Fibers (BEDFs) have been demonstrated and the reasons of this phenomenon are explained. The possibility of temperature sensor based BEDFs has also been discussed.
FBG inscribed on splice joint is proposed to be used as a sensor. It could realize temperature and strain measurement simultaneously because of the different strain responses of the different parts of the FBG inscribed on splice joint, while the temperature responses are same. The strain responses of four overlap values are discussed, which is used to optimize the discrimination capability of the...
Fiber Bragg grating(FBG) written in rotated fused polarization maintaining(RF-PM) fiber is proposed. The fiber structure constructs two Fabry-Perot interferometers. The spectral characteristics is analyzed and simulated. The Bragg reflection spectrum of fiber subjected to different loading angles are measured as the rotated fused angle is 22.5°. The experimental results show that the asymmetrical...
Accurate downlink channel state information at the transmitter (CSIT) is essential to utilize the benefit of 3D Massive MIMO/FD-MIMO systems. Conventional approaches to obtain CSIT for FDD MIMO systems require downlink training and CSI feedback. However, such training will cause a large overhead for 3D Massive MIMO/FD-MIMO systems because of the large dimensionality of the channel matrix. In this...
Urban traffic congestion state detection has been a problem of concern at home and abroad. The mainstream and traditional ways to detect traffic congestion state include manual survey, fixed traffic information collection technology and mobile traffic information collection technology. These methods all have obvious flaws such as the sample size of these methods is limited and additional equipment...
We demonstrate InP-based high power modified uni-traveling carrier photodiodes heterogeneously integrated on silicon on diamond (SOD) waveguides. These photodiodes reach 20 nA dark current at −5 V bias voltage. A 50 μm long device exhibits an internal responsivity of 1.07 A/W. The bandwidths of the devices with 14×25 μm2, 14×50 μm2, 14×100 μm2 and 14×150 μm2 area are 22 GHz, 16 GHz, 10 GHz and 7 GHz,...
Initial access is the process whereby a mobile user connects to the cellular network since it is switched on, wherein cell search (CS) over the downlink and random access (RA) on the uplink are the two major steps. The highly directional communication in millimeter wave (mmWave) cellular networks requires the user and the base station (BS) to find and agree upon a suitable beamforming (BF) direction...
Full-Dimension MIMO (FD-MIMO) technology has been shown to increase spectral efficiency 2-4X compared to current LTE systems by exploiting a large number of antennas to support high order multiuser MIMO. High order multiuser MIMO with large number of antennas increase design and implementation complexity significantly. Furthermore, practical challenges such as antenna calibration for RF mismatches...
Modular multilevel converter (MMC) is a promising converter in medium and high voltage applications due to its modularity and easiness to meet any voltage level by cascading the sub-modules. However, large amount of modules not only increase the failure probability of the devices, but also increase the difficulty of the fault diagnosis, which have brought a challenging for popularization and application...
A new brushless doubly-fed double stator double rotor (DSDR) generator based on permanent magnet field modulation for the wind power application is proposed in this paper. This generator adopted double stator to achieve the decoupling of the control winding and power winding. To improve the power density, a freely rotating rotor is introduced. To achieve the variable-speed constant-frequency operation...
A novel hybrid five-level voltage source converter for high-efficiency applications is presented and investigated in this paper, and the topology configuration is based on the upgrade of three-level T-type converter and two-level converter. Compared with traditional stacked multilevel converter and flying capacitor multilevel converter, this hybrid multilevel converter generates desired staircase...
In modern networks, there exist different applications which generate various different types of network traffic. In order to improve the performance of network management, it is important to identify and classify the internet traffic. The machine learning (ML) technique based on per-flow statistics has been widely used in traffic classification. Different from traditional classification methods,...
The increasing of mobile devices results in the recent mobile big data era. A large number of useful information can be extracted from mobile big data. Extracting the residents' activity information from mobile big data is more and more popular in recent years because of its lower cost and higher accuracy. In this paper, we propose an algorithm to mine some meaningful residents' activity information...
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.