Jiang W.,Shenyang University of Technology |
Li X.-X.,Shenyang University of Technology |
Liu L.-M.,Shenyang University of Technology
Physica E: Low-Dimensional Systems and Nanostructures | Year: 2013
A multilayer and multisublattice cubic nanowire is studied based on a shell/core and the effective-field theory. The formulas of the longitudinal and transverse magnetization for each sublattice of the nanowire are given. The surface parameters have intense effects on the magnetizations and phase diagrams (phase transition temperatures and compensation temperatures) of the system. Two compensation points do exist for certain values of the surface transverse field, the surface single-ion anisotropy and the surface exchange coupling in the system. This interesting phenomenon may be potential applications in information storage technology. © 2013 Elsevier B.V.
Wang S.,Shenyang University of Technology
Mathematical Problems in Engineering | Year: 2013
A mechanical component may fail in many modes that are usually not independent. There is generally not a joint probability density function to describe these correlated failure modes. Thus, it is difficult to compute the reliability when considering the correlations between the failure modes. It is supposed that three or more failure modes arise synchronously to be a very small probability event. The relationship between ultimate state functions in different failure modes is established by utilizing linear regression method. A double integration model for reliability of mechanical components with dependent failure modes is built according to stress-strength interference model. In case of square, cube, or exponential relationship between two ultimate state functions, a linear transformation is made. An example of pin that may fail in shear fracture, bruise, or both is discussed. The reliability is compared with that obtained by usingMonte Carlomethod, which represents that the reliabilitymodel with dependent failure modes proposed is correct. Copyright © 2013 ShijieWang.
Chen D.H.,Tokyo University of Science |
Yang L.,Shenyang University of Technology
Composite Structures | Year: 2011
In this report, elastic moduli of honeycomb consisting of asymmetrical hexagonal cells are studied by using a theoretical approach and the finite element method (FEM). Based on the change in the shape of the hexagonal cell, explicit equations describing the equivalent elastic moduli of honeycomb with cell wall parallel to the y-axis are proposed. In the analysis of honeycomb deformation, the shear deformation was considered in addition to bending deformation and tensile deformation. As a result, the equivalent elastic moduli could be calculated with extremely high precision. © 2010 Elsevier Ltd.
Wang F.,Shenyang University of Technology
Diangong Jishu Xuebao/Transactions of China Electrotechnical Society | Year: 2012
Permanent magnet (PM) machine has advantages of high power density, high efficiency and high reliability, and has been using widely in the wind power generation systems. However, the PM wind generators face the challenge of how to increase the ratio of performance to the cost due to the expensive rare earth PM material. In this paper, based on the comparative study on the feature and performance of PM generators for high speed, medium speed and low speed direct-driven wind power generation systems, the key design techniques of PM wind generators are explained. The influence of machine structure and combination of pole-slot number on the performance, the prevention of permanent magnet from demagnetizing, and the reasonable matching between generator and converter are analyzed. Besides, the development tendency of design and control technology of the PM wind power generators is discussed.
Yuan W.,Shenyang University of Technology |
Liu B.,Shenyang University of Technology
Yi Qi Yi Biao Xue Bao/Chinese Journal of Scientific Instrument | Year: 2013
Aiming at the problems that the fixed focus iris recognition system with extended depth of field can easily introduce defocused iris images with different defocusing degrees and increase the recognition error rate, this paper proposes a stable feature fusion solution. Taking the image sequence based defocused iris recognition method as the basis for analysis and verification, the proposed method statistically studies the distribution rules of the stable features in spatial domain and frequency domain under different image defocusing degrees, determines the extraction rules of the stable dark region features and stable Fourier low frequency phase features based on single image registration, fuses them in the matching score level, and finally achieves the recognition. The SUT-DI defocused iris image database was used as the benchmark to carry out experiment. The experimental results show that, compared with the method based on single feature before fusion and the method based on image sequence, the proposed method achieves better recognition performance, and the equal error rate is reduced by 7.77% at most, which proves that the proposed method has robustness to the image optical defocusing, and is able to provide the technical support for the development of portable iris recognition system.
Li F.,Shenyang University of Technology |
Xie H.-L.,Northeastern University China
International Journal of Automation and Computing | Year: 2010
A visual servoing tracking controller is proposed based on the sliding mode control theory in order to achieve strong robustness against parameter variations and external disturbances. A sliding plane with time delay compensation is presented by the pre-estimate of states. To reduce the chattering of the sliding mode controller, a modified exponential reaching law and hyperbolic tangent function are applied to the design of visual controller and robot joint controller. Simulation results show that the visual servoing control scheme is robust and has good tracking performance. © 2010 Institute of Automation, Chinese Academy of Sciences and Springer-Verlag Berlin Heidelberg.
Wang Y.,Shenyang University of Technology
Advanced Materials Research | Year: 2012
A novel clay containing a heterogenized Ce(SO 4) 2 complex (Ce-bentonite) has been prepared via ion exchange of a Chinese N a +-bentonite with pillared layer clay complex. It was established that the active species [Ce(OH) 3] + was situated on the external surface of the catalyst, which was found to be efficient in the liquid-phase esterification of acetic acid with 2-methoxyethanol.
Liu G.-L.,Shenyang University of Technology
Wuli Xuebao/Acta Physica Sinica | Year: 2010
The electronic structure of Mg alloy was calculated with the recursion method. The result shows that the density of states of Mg in grain is similar to that on the surface of Mg alloy, but it is obviously different when O or O, H atoms exist on the surface of Mg alloys. This indicates Mg has similar properties whether in grain or on surface, but the properties of Mg change apparently after oxygen or hydrogen atom permeated in the surface layer of Mg alloy. Al, Y or La atom diffuses from grain to the surface and segregates there, because each the doped atom embedding energy of Al, Y or La atom on the surface is lower than that in grain. The affinity energy of Al-O, Y-O, La-O, Mg-O, Mg-O-H is negative, so they can form compound. Because the affinity energy of Mg-O-H is lower than that of Mg-O, Mg(OH)2 is more stable than MgO. In the early stage of oxidation, oxygen combined with Mg, Al, Y or La forming oxide. When Mg alloy is in corrosive medium, MgO reacts with H2O forming Mg(OH)2. Al2O3, (Y, La)2O3 and Mg(OH)2 can protect Mg alloys from corrosion and improve corrosion resistance. ©2010 Chin.Phys.Soc.
Wang Y.,Shenyang University of Technology
Advanced Materials Research | Year: 2012
This document explains and demonstrates the problem of butanol and propylene oxide propoxylation, ZrO 2 load active alkali metal oxides MgO the catalytic propoxylation method, analyzed a new type of catalyst activity and selectivity. The results show that the synthesis of ZM complex oxide as a catalyst for the reaction of butanol substrate, through the catalytic reaction of propylene oxide, selective access to the propylene glycol ether, High selectivity synthesis 1-butoxy-2-propanol. Synthesis of complex oxide catalyst ZM series in the course of the performance of the primary ether good selectivity, Primary ether, second ether ratio greater than 12, and the catalytic activity is also high (about 90% of all).
Northeastern University China and Shenyang University of Technology | Date: 2014-12-12
Provided are a double auxiliary resonant commutated pole three-phase soft-switching inverter circuit and a modulation method. The circuit includes a three-phase main inverter circuit and a three-phase double auxiliary resonant commutator circuit. An A-phase double auxiliary resonant commutator circuit, an A-phase main inverter circuit, a B-phase double auxiliary resonant commutator circuit, a B-phase main inverter circuit, a C-phase double auxiliary resonant commutator circuit and a C-phase main inverter circuit are connected in parallel in sequence and simultaneously connected with a DC power supply in parallel. The present invention can achieve the separation of the resonant current of the double auxiliary resonant commutator circuit from the load current at the moment of current commutation, thereby effectively reducing the current stress of the auxiliary switching tubes and the efficiency can be greatly increased particularly under light load condition.