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.
The thin-walled parts of the tank are widely used in aerospace filed and the accuracy is the basis requirement for ensuring the usability. Due to the low rigidity of the thin-walled parts, the milling force becomes a major factor for the machining deformation. Based on analysis the relationship between feed speed and the length of the cutting arc, the feed speed optimization method is proposed to...
We experimentally demonstrated an erbium-doped fiber amplifier for OAM modes using an annular-core photonic lantern. The small signal gain for OAM modes with |L| = m1 and 2 are obtained to be 22.1dB and 16.7dB.
In this work, information security of a cooperative wireless communication system over three-phase amplify-and-forward (AF) two-way relaying channels is investigated. A relay power allocation scheme is proposed to improve secrecy capacity of the system. We first derive the secrecy rate expression for the basic scenario which consists of one source, one destination, one single relay, and an eavesdropper...
In this paper, we study the energy-efficient user access control (UAC) based on resource allocation (RA) in heterogeneous cellular networks (HCNs) with the required downlink data rate under non-ideal power amplifiers (PAs) and circuit power. It is proved that the energy consumption minimization is achieved when the typical user accesses only one base station (BS), while the other BSs remain in idle...
Cooperative receiving has been recognized as an effective technique to mitigate inter-cell interference (ICI) for the uplink of multicell wireless systems. However, how to cluster the cooperative cells effectively is critical to the subsequent multicell signal processing and the corresponding performance improvement. A dynamic user-centric clustering scheme based on the interference channel strength...
A novel radial basis function neural network (RBF-NN) modeling method is presented for the reactor-regenerator system of fluid catalytic cracking unit (FCCU). In which, the improved cuckoo search (ICS) algorithm is proposed for the RBF-NN training problem. In the ICS, the mutation operator with adaptive step size and a self-learning selection strategy are used to improve solution accuracy. The numerical...
The design of improved fault location system and its experimental test system is presented in this paper. The fault location system is based on traveling waves and contains several innovative algorithms, considering the main influential factors such as the uncertainty of wave speed and the accuracy of transmission line length. Besides, the design of experimental system for testing the location precision...
In this paper, a comprehensive friction model for collaborative industrial robot joints is proposed which takes into account the velocity, temperature and load torque effects. The model indicates that the velocity and temperature have a strong influence on viscous friction nonlinearly, whereas load torque significantly influences the Coulomb friction linearly and causes a slight Stribeck effect. The...
The Visible Light Communication (VLC) is a good candidate technology for the application of Intelligent Transportation System (ITS). This paper focuses on typical application scenario between the traffic lights and lorry fleet. Based on the theoretical analysis and numerical calculation, we get the relationship between the speed of the lorry fleet and the conversion time of the traffic lights. The...
Because of the development of computer networks and the scattered locations of system, distributed data-storage system is widely deployed. Data partition and redundant strategy determine the space utilization, access performance and data reliability of the storage system. Based on the analysis of current data partition and redundant mechanisms, we propose a novel Consistent Hash Based Flexible Redundant...
In this manuscript, an Inverse Synthetic Aperture LADAR (ISAL) system at 1.55 μm wavelength is introduced. We have recently completed an imaging experiment on real target 1.1 km away from laser radar by using the system and obtained a series of images of the target, an aircraft model, with cm-level range resolution and mm-level cross-range resolution, which is due to the large bandwidth transmitting...
In this paper, an integral sliding mode based tracking control (ISMTC) scheme is proposed for a marine surface vehicle (MSV) in order to achieve accurate tracking performance. Salient features of the ISMTC scheme are as follows: (1) The integral sliding mode (ISM) technique is employed to realize accurate tracking performance, whereby a finite-time unknown observer is designed and integrated into...
Synthetic aperture ladar (SAL) is a new remote sensing sensor and has the potential for much finer resolution than synthetic aperture radar (SAR) for its much shorter wavelength. For SAL system, frequency modulated continuous wave (FMCW) is usually used to achieve large time-bandwidth product (TBP). In this paper, we proposed the method for focusing the FMCW-SAL data. Firstly, we derived the signal...
The environmental factor (such as temperature, etc.) is an important error sources of product performance degradation data. In practice, the raw degradation data usually contain some noise terms caused by the fluctuation of environmental factor. Therefore, it is necessary to extract the real degradation trend before degradation modeling and life prediction. In this research, the Grey relational analysis...
This paper addressed the retrieval of land surface temperature (LST) from combined mid-infrared and thermal infrared data of the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard the Suomi National Polar-Orbiting Partnership (S-NPP). To efficiently remove the effect of the direct solar radiance, a relationship between direct solar radiance and water vapor content, view zenith angle and solar...
In this study, the automatic reflectance-based method is used to vicarious radiometrically calibrate the satellite optical sensors using the desert target located in the Baotou site in China. The ground reflected radiance of the desert target were collected automatically using an automatic observation system. The reflectance of the desert target was calculated with the radiance collected with the...
This invited talk will present recent highlights from our research on two-dimensional (2D) materials including graphene, boron nitride (h-BN), and transition metal dichalcogenides (TMDs). The results span from fundamental measurements and simulations, to device- and several unusual system-oriented applications which take advantage of unique 2D material properties. Basic electrical, thermal, and thermoelectric...
This paper addresses the problem of trajectory tracking control for an unmanned surface vehicle(USV) with unknown disturbances and input saturation. Let the saturation function is divided into a smooth function and a bounded function, the saturation function can be approximated by smooth function and the bounded function which can be treated as a system uncertainty. An auxiliary design system is employed...
This paper addresses robust leader-follower formation control problem with prescribed performance and collision avoidance for a group of fully actuated unmanned surface vehicles (USVs). The dynamic surface control (DSC) technique is employed to introduce a first-order low-pass filter in the kinematic design such that the utilization on the leader vehicle's acceleration is avoided in the kinetics control...
The hybrid of the fuel cell (FC) and Super-capacitor (SC) for Hybrid Electric Vehicle (HEV) is beneficial to compensate the slow dynamic response and avoid reactant starvation of FC. Energy management system (EMS) is critical to the HEV and a fuzzy controller plus low pass filter is proposed to prolong the FC lifetime and decrease hydrogen consumption. The constrained bi-objective fuzzy EMS optimization...
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.