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Mechanical property test of marine components has the characteristics of complicated structure, diverse testing resources, varied testing environment, high testing cost and long cycle. Firstly, the transfer function of the servo control system is established on the basis of considering the non-linear factors of the test platform. Secondly, a measurement and control system framework combining the centralized...
A relational table over a set of attributes can be mapped onto a multi-dimensional array and stored as such. Such a conceptual view of relations lends itself to easy formulations of numerous analytical algorithms. This is the view taken in the representation of relations in data-warehousing to support On-Line Analytical Processing (OLAP). The main drawback of such a storage scheme is that the equivalent...
The problem of compressed sensing (CS) is considered in two-dimensional (2D) sparse decomposition measurement model. Correspondingly, a novel recovery algorithm — modified 2D subspace pursuit (M-2DSP) algorithm is proposed with the available prior support and chunk sparse structure. The massive multi-input multi-out (MIMO) system show a concealed sparse structure and temporal correlation in the user...
Pilot contamination caused by non-orthogonal pilot sequences reuse in adjacent cells has become one of the main impairments for massive multiple-input multiple-output (MIMO) systems. A scheme named flexible pilot reuse is proposed in this paper to reduce the effect. The main idea is that users suffered from mild pilot contamination (PC) are allocated the same set of orthogonal pilots, while the users...
This paper studies the downlink sum-rate and energy efficiency (EE) of massive multiple-input multiple-output (MIMO) systems under the effect of channel aging caused by the movements of users. First, a closed-form expression of the downlink sum-rate where zero-forcing (ZF) precoder is adopted at the base station (BS) is derived. Based on the expression, the power-scaling law that when the number of...
The tradeoff between the dexterity, compliance and payload capacity is a key challenge in the design of Hyper-Dexterous Manipulator (HDM). In this paper, we focus on the properties of typical biological structures related to HDM in order to guide the design of a high performance HDM, as biological inspiration provides a key design guideline for robotic design. The typical biological structures are...
Continuum manipulators can exhibit behaviors similar to snakes, elephant's trunks, and octopus tentacles, which possess incredible dexterity and intrinsic compliance for safe interaction with unstructured environments. However, the lack of enough stiffness limits their scope and application. In this paper, we introduce four different structures of continuum manipulators, including a simple structure...
Sparse representation is capable of modeling signals as linear combination of a few atoms from a pre-trained dictionary. It allows learning an adaptive dictionary that leads to highly sparse nature in the representation of signals. In this paper, sparse representation is deployed in a lossy hyperspectral data compression framework. Dictionaries that exploit spectral correlation, as well as both spectral...
In this study, oriented rutile TiO2 nanorod arrays (NRAs) were directly grown on the titanium (Ti) thin films deposited on the Si substrate in a low concentration of hydrochloric acid aqueous solution vapor environment called acid vapor oxidation (AVO) process which is a facile and environmentally friendly hydrothermal route without using any catalysts, seeds or templates. The growth of the TiO2 NRAs...
Three-dimensional TiO2 with nanoscale structures, such as porous films, porous spheres, and hierarchical structures, play a promising role in the fields of gas sensors. In this work, hierarchical TiO2 shaped like dandelion are synthesized by hydrothermal process. The dandelion-like nanostructured TiO2 is analyzed by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). Then...
We investigate channel estimation mean square error (MSE) performance in Massive multiple-input multiple-output (MIMO) system with pilot contamination. Different from the traditional MSE expressions, the expressions that we derived have algebraic form, which no longer need hard matrix inversion as M, the number of the base station antennas, increasing. From them, we also found that the average transmitted...
The surface roughness and the subsurface damage introduced by manufacturing procedures are important factors affecting the mechanical and optical properties of the optical components. To obtain the relationships between the subsurface damage parameters and optical properties, we study on the influence of grinding process parameters (average abrasive size, grinding force, wheel speed, grinding depth)...
Rural commercial banks in China originate from the shareholding reform of rural credit cooperatives. The financial governance subjects of China's rural commercial banks reallocate the financial decision-making power, executive power and supervisory power according to their own governance objectives, and different levels of financial governance efficiency are reflected during the process. We take China's...
To build potentiometric SO2 gas sensors based on Li3PO4 electrolyte thin film, prototypes with different structures and electrode materials are investigated. The structures of the SO2 sensors can be described as followings, O2, SO2, Au, Li2SO4-V2O5/Li3PO4/Li2TiO3-TiO2, Au, SO2, O2 with 600 °C thermal treatment temperature of RE (reference electrode) and 500 °C thermal treatment temperature of WE (working...
Based on the subsurface damage model and the material removal rate of K9 glass in HF acid solution, a fast method was proposed to calculate a set of parameters to characterize the subsurface damage of a polished sample. When micro cracks of the etched sample's subsurface can be clearly observed, by using image processing, lengths, widths, angles, densities of the micro cracks can be calculated and...
Switched reluctance motor (SRM) system is a very highly nonlinear control system. While the traditional magnetic circuit methods and the analytical methods are hard to analyze the dynamic process of the motor, in order to improve the analysis precision, the two-dimensional transient electromagnetic field model is built in ANSOFT platform, and the control circuit model is built in SIMPLORER platform...
This paper studies the asymptotic capacity of large MIMO amplify-and-forward (AF) relay networks with one source-destination pair equipped with M antennas and K single-antenna relays. In contrast to prior works, we consider not only the multipath fading but also the path loss effect. By using random matrix theory, we first derive the asymptotic eigenvalue distribution (A.E.D.) of the channel covariance...
Rotation modulation is an effective method of reducing the errors of inertial navigation system (INS). However, when the carrier is in angular motion status, especially when the heading angle changes in wide range, the performance of error suppression will be influenced. In this paper, according to the error rotation modulation principle, based on attitude error equation of rotation inertial navigation...
This paper presents a method for calculating iron losses in three-phase induction motors under the inverter supply through the field-circuit coupled time-stepping finite element method (FEM). Iron losses are calculated by using the three-term iron losses separated model and modifying the loss coefficients obtained by the iron losses curves which are provided by the manufacturer under the sinusoidal...
To characterize the subsurface mechanical damage (SSD) of the polished optics, the material remove rate of the polished K9 glasses based on HF acid etching was investigated. The etching of optics is assumed to be isotropic, a polished K9 sample with special designed pattern was tested to find out the constancy of etching rate versus time. As the etching rate was determined, the polished samples were...
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