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In this paper, a method is proposed for detection and estimation of high-resistance connection (HRC) for permanent magnet synchronous machine (PMSM) derives. The method is based on the relationship between the zero sequence voltage components (ZSVC), the stator currents and the resistance deviation of each phase winding. In the proposed method, the HRC fault detection, fault severity estimation and...
This paper discusses the performance model for practical computational fluid dynamics (CFD) simulation. Based on the analysis of the conventional qualitative model and empirical knowledge in the simulation, a set of practical models for the linear solution in high-order finite element method (FEM) simulation are established: a linear function model for the storage consumption, and a power function...
OpenFOAM is a framework of the open source C CFD toolbox for flexible engineering simulation, which uses finite volume method (FVM) in the discretization of partial differential equations (PDEs). The problem solving procedure in OpenFOAM consists in equations dicretization stage, equations solving stage and field limiting stage. The best parallelism is limited by the equation solving stage, which...
Recent advances in deep learning have shown exciting promise in filling large holes in natural images with semantically plausible and context aware details, impacting fundamental image manipulation tasks such as object removal. While these learning-based methods are significantly more effective in capturing high-level features than prior techniques, they can only handle very low-resolution inputs...
In this study, the feedback controllers were designed and implemented to fulfill the constant-voltage (CV) and constant-current (CC) output modes for a power converter. This converter's power stage was composed of a stand-by power, power factor corrector, and DC-DC converter. The topology used by the DC-DC converter was a phase-shifted full-bridge with a parallel current-doubler rectification converter...
Cloud computing is a scale-based platform, provides several kinds flexible resources such as storage, databases and computing power, requires more virtual machines(VMs) and consumes lots of electricity resource, which is suitable to execute workflow applications. However, with the increasing scale of data centers, the energy consumption problem has become one of the major concerns in clouds. To address...
In order to realize the functional requirements of hydraulic cylinder installing in the leg of the rehabilitation robots, a new type of servo rotary valve was designed with an introduction of its structure. The spool in rotary valve may have different locations when the actual working conditions are different. To know the flow field of rotary valve above case we have done a thorough numerical analysis...
A power converter supplying kilo-watt-power from its output side is developed in this paper. The composition of its power-stage includes an AC-DC converter and a DC-DC converter. The topology used by the DC-DC converter is the phase-shifted full-bridge with parallel current-doubler rectification converter (PSFB-PCDRC). For the sake of feedback controller design, the small-signal model of PSFB-PCDRC...
The present work studies the influence of Maxwell stress on a straight but non-linear polarization saturation (PS) crack in a 2D piezoelectric material under combined mechanical and electric loadings at infinity. The non-linear piezoelectric fracture mechanics model, which is the PS model, is adopted in this paper. It is assumed that the crack is electrically semi-permeable. Based on the Stroh's formalism...
This paper focuses on mesh-partitioning metrics in large-scale parallel computational fluid dynamics (CFD) simulations. Mesh partitioning has a significant influence on the efficiency of parallel preconditioned conjugated gradient (PCG) solving procedure, which is the most representative and timeconsuming part in parallel CFD. As the efficiency of parallel PCG depends on load balancing, communication...
The discrete topology optimization method is widely used because of its high degree of freedom and high problem-solving efficiency. However, one of its main drawbacks is that the output graphic is constituted of a 0–1 matrix leading to rough boundaries and implicit structures, which are difficult to be manufactured. Aiming to transform the implicit rough boundary into the explicit smooth boundary...
Solar is a kind of new energy, and photovoltaic power generation is an important way of distributed generation; FREEDM system is a kind of Energy Internet model, which is presented by Professor Alex Q. Huang from North Carolina State University in 2008. Combining the advantages of photovoltaic power generation and FREEDM system, this paper proposes a kind of grid-connected photovoltaic power generation...
A quasi-optical mode converter, consisting of a helically corrugated launcher and a few curved mirrors, for a TE5,3 mode gyrotron is proposed in this paper. Applying the geometric optics approximation and the vector diffraction theory, a numerical simulation code of the mirrors system is developed. Simulation results show that the vector Gaussian mode content in the window plane more than 95% has...
Pedestrian dead reckoning (PDR) is a promising solution for indoor positioning. It can work without either GPS signals or Wi-Fi coverage. Commonly, a foot mounted PDR system is relatively more accurate, but a PDR system mounted on the waist or integrated in a Smartphone can be more convenient. However, such systems have difficulties with step length estimation. Most of them estimate step length indirectly...
In recent years, the amount of mass data has been increased so much that a high performance distributive database to compute the price would be high while guaranteeing the robustness and scalability. To solve this problem, this paper designs an intelligent system for large scale database processing-oriented parallel database engine. Distribution and parallel computing in this system are taken into...
Resources management is the most important part of the cloud computing. This paper introduces the lifecycle of cloud bank which based on existing cloud bank model and present the proper pricing strategy. It was according to the features of cloud bank in different periods. The purpose of this paper is to provide an automatic updating mechanism to pricing the cloud resources and maximizing the benefit...
Focused ultrasound (FUS) thermal therapy relies on temperature imaging for treatment monitoring and guidance. Current ultrasonic temperature estimation mainly involves the detection of echo-time shifts using cross-correlation processing between segmented radio-frequency (RF) data pre- and post-FUS heating. Generally, a minimum RF data segment of around 6 wavelengths is required to obtain accurate...
Cloud computing arise as an efficient way to allocate resources for execution of task and services within a set of geographically dispersed providers from different organizations. In cloud computing, an IaaS computing model called Cloud Bank. Cloud Bank model [1] is an IaaS model on the basis of economics principal and cloud computing features. It can be partly distinguished from other traditional...
In order to solve the gear reducer first selection design basis, the problem of insufficient, apply optimized design theory, write gear reducer first selection design mathematical model. Use level 2 incLined gear reducer as an example, write MATLAB and graphic interface, summarizes the total ratio under different conditions, power and reducer total of center distance change rule.
Due to increase in location based services, the need for efficient network based location methods has been made of paramount of importance. Among the mobile positioning techniques Time of Arrival (TOA) and Time Difference of Arrival (TDOA) arisen as promising techniques. In order to deal with such technology some theoretical approaches have been put forward to draw the estimation under the technological...
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