Science Discovery

Volume 5, Issue 1, February 2017

  • Research of Vortex Nucleation in Bose-Einstein Condensates

    Li Ji, Ren Yuan, Shao Qiongling

    Issue: Volume 5, Issue 1, February 2017
    Pages: 1-6
    Received: Mar. 13, 2017
    Accepted:
    Published: Mar. 15, 2017
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    Abstract: Vortex nucleation is the key technology to realize quantum gyroscope in Bose-Einstein Condensates (BEC). Through mass investigation and research, the recent research status of vortex nucleation in Bose-Einstein Condensates is presented, the theory and experimentation about imprinting phase, rotating the potential trap and transferring the orbital a... Show More
  • Research of Numerical Simulation on Perforation of Conical Nose Rigid Projectile into Alluminum Alloy Target

    Xu Ruihuai

    Issue: Volume 5, Issue 1, February 2017
    Pages: 7-11
    Received: Mar. 13, 2017
    Accepted:
    Published: Mar. 15, 2017
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    Abstract: In this paper,the penetration and perforation process of the conical nose rigid projectile into alluminum alloy target were simulated numerically by using FEM. Two sets of the projectiles and targets in different sizes were used in calculation models. The first set took the same size as the tested projectile and target for comparison, the second se... Show More
  • Investigation on Application of Support Vector Machine Algorithm in the Experimental Simulation System for Mechanism Motion Reliability

    Zhang Tong, Li Sen, Qiao Jia-dong

    Issue: Volume 5, Issue 1, February 2017
    Pages: 12-18
    Received: Mar. 13, 2017
    Accepted:
    Published: Mar. 15, 2017
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    Abstract: The complexity of the mechanism brings great difficulty to the calculation of the mechanism motion reliability, and the computer simulation algorithm based on Monte Carlo method needs a great number of simulation. The further-development of LMS Virtual. Lab was carried out, and the least square support vector machine algorithm was used to construct... Show More
  • Distributed Grid-Connected Photovoltaic (pv) Research on the Influence of Power Distribution Network Voltage

    Yuan An, Hongxin Liu

    Issue: Volume 5, Issue 1, February 2017
    Pages: 19-24
    Received: Mar. 29, 2017
    Accepted:
    Published: Mar. 31, 2017
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    Abstract: For the study of distributed grid-connected photovoltaic (pv) affect the quality of power distribution network voltage. Application Matlab respectively different access points in the access of distributed photovoltaic (pv) power distribution network, different capacity and power factor to carry on the simulation. Analysis the influence of distribut... Show More
  • Research on Sparse Targets Detection Methods Based on GLRT in Non-Gaussian Clutter

    Gu Xinfeng, Yan Shuqiang, Hao Xiaolin, Huang Kun

    Issue: Volume 5, Issue 1, February 2017
    Pages: 25-32
    Received: Mar. 29, 2017
    Accepted:
    Published: Mar. 31, 2017
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    Abstract: For the problem of detecting range-spread target with spare scatterers in non-Gaussian clutter modeled as spherically invariant random vector(SIRV). Firstly, it is assumed that the number of the target scatterers is known and a generalized likelihood ratio test detector based on scatterers number (SN-GLRT) is proposed. Then a sparse scatterers targ... Show More
  • Permanent Magnet Synchronous Motor Direct Torque Control Based on Stator Resistance Online Estimation

    Du Xue, Zhang Suying, Jin Ji, Zhao Peidi, Liu Huixian

    Issue: Volume 5, Issue 1, February 2017
    Pages: 33-39
    Received: Apr. 11, 2017
    Accepted:
    Published: Apr. 12, 2017
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    Abstract: Permanent magnet synchronous motor direct torque control system is characterized by its fast, automatic control and so on. Based on the actual value and reference value of the motor control system, this article analysis the effect of the stator resistance variation on the performance of the system.A method to track stator resistance variation is pr... Show More
  • Research on Fast Soft Shadow Algorithm Based on 4D Rasterization

    Zhao Qi, Wang Lili

    Issue: Volume 5, Issue 1, February 2017
    Pages: 40-47
    Received: Apr. 11, 2017
    Accepted:
    Published: Apr. 12, 2017
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    Abstract: This paper introduces an algorithm that extends traditional 2D projection and rasterization to 4D space for fast soft shadow rendering. First, the rectangular area light source is seen as a point light source that translates with two degrees of freedom. As the point light source moving, the projections of the triangles and the output image samples ... Show More
  • Range-Spread Target Adaptive Detector for Non-Gaussian Clutter

    Gu Xinfeng, Hao Xiaolin, Liu Tongling, Yang Ganlin, Li Xinxing

    Issue: Volume 5, Issue 1, February 2017
    Pages: 48-52
    Received: Apr. 11, 2017
    Accepted:
    Published: Apr. 12, 2017
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    Abstract: This paper addresses range-spread target detection in non-Gaussian clutter modeled as spherically invariant random vector clutter (SIRV). A adaptive modified scatterer density dependent (AMSDD) detector based on clutter power is addressed for the problem that MSDD has detection loss when falsely estimating the number of scatterers. Firstly, it esti... Show More
  • Investigation on the Microstructure and Mechanical Properties of Dissimilar Weld Joint for Inconel 617 Alloy and 12Cr Steel

    Wang Peng, Xu Huali, Liu Xia

    Issue: Volume 5, Issue 1, February 2017
    Pages: 53-58
    Received: Apr. 11, 2017
    Accepted:
    Published: Apr. 12, 2017
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    Abstract: The Inconel 617 nickel base alloy and 12Cr steel were welded by auto-TIG welding method, the microstructure and mechanical properties of dissimilar weld joint were investigated. The results showed that the optimized TIG welding process could obtain no defect dissimilar weld joint. Characterization on the microstructure of the weld joint showed that... Show More
  • Study on the Yoshida-Uemori Material Model of High-Tensile Steel Sheets by Shear Tests

    Chih-Yi Chang, Ming-Hsiung Ho

    Issue: Volume 5, Issue 1, February 2017
    Pages: 59-68
    Received: Apr. 20, 2017
    Accepted:
    Published: Apr. 20, 2017
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    Abstract: In this research, the Yoshida-Uemori material models for four kinds of high-tensile steel sheet were analyzed by shear tests. The Yoshida-Uemori (Y-U) material model is currently the most important model in the simulation of stamp forming high-tensile steel sheets. It can comprehensively describe the Bauschinger effect and strain hardening behavior... Show More
  • Research on Feasibility of Large-scale New Energy Islanding Detection Scheme Based on Impedance Measurement

    Wang Miao

    Issue: Volume 5, Issue 1, February 2017
    Pages: 69-76
    Received: Apr. 20, 2017
    Accepted:
    Published: Apr. 20, 2017
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    Abstract: A lot of research has been done on islanding detection of photovoltaic(PV) power system. In these schemes, islanding can be detected by schemes based on convertor control. The range of these research is islanding occurs in a single power station or distributed generation system. However, experiments proof that islanding also occurs in large-scale w... Show More