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Improved Quantum-Behaved Particle Swarm Method for Optimizing Complex Thin Plate Structure
Weitao Cheng,Yixiao Qin,Jinpeng Gu,Haibiao Gao,Yue Yan,Junle Yang,Yang Chen,Shen Su,Kaiyao Yang 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.4
A large number of heavy-duty asymmetric thin-plate box girder structures exist in large equipment, and their optimization can reduce the amount of material used and increase their load-carrying capacity. A new optimization method based on the Improved Quantum-Behaved Particle Swarm Optimization method (IQBPSO) is proposed in order to efficiently solve the mathematical model for the rationalization and optimization design of structures. The penalty function and Lévy flight strategy are considered in the optimization design of the improved algorithm, thus transforming the constrained optimization problem into an unconstrained optimization problem and improving the diversity and local optimization search capability of the quantum particle swarm. A mathematical model for the optimal design of box girder section size is established with the reduction of beam cross-sectional area as the objective function and the thin plate strength, rigidity, and stability of the thin slab as the constraints. The rapid lightweight design of the thin plate box beam was achieved, resulting in a 9.6% reduction in the manufacturing cost of the thin plate box beam. The optimization results are compared with several solutions of the thin slab box beams to verify the reliability and validity of the proposed optimization method.
Deng Weitao,Fu Xin,Tang Jiayi,Zhang Xiuyun,Cheng Wangbin 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.3
The rotation vector of the matrix converter has the characteristic that the common mode voltage is zero, so the direct torque control (DTC) strategy using the rotation vector can effectively suppress the common mode voltage of the motor system. However, because the direction of the rotation vector is constantly changing and the distribution is extremely uneven, the existing DTC based on the rotation vector not only has a complicated switching table, but also increases the torque ripple and current harmonics. In this paper, a novel direct torque control strategy using virtual rotation vectors is proposed. The virtual rotation vector is synthesized by the rotation vector with identical rotating direction, and the duty cycle of the selected rotation vector is theoretically derived and calculated, leading to six evenly distributed virtual rotation vectors with fixed relative positions, and therefore a simple-form switching table can be easily constructed. The proposed control strategy is experimentally verified, and the results show that, compared with the traditional rotation vector-based DTC, the proposed strategy not only achieves zero common-mode voltage, but also significantly reduces torque ripple and current harmonics, improving the steady-state performance of the motor system.
Zhang, Xinxin,Cheng, Shiyang,Zhang, Wei,Zhang, Cai,Drewett, Nicholas E.,Wang, Xiyang,Wang, Dong,Yoo, Seung Jo,Kim, Jin-Gyu,Zheng, Weitao American Chemical Society 2017 INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH - Vol.56 No.39
<P>Ag/Pr<SUB>6</SUB>O<SUB>11</SUB> catalysts supported by either Pr<SUB>6</SUB>O<SUB>11</SUB> nanorods (Pr<SUB>6</SUB>O<SUB>11</SUB>-NRs) or nanoparticles (Pr<SUB>6</SUB>O<SUB>11</SUB>-NPs) were prepared by conventional incipient wetness impregnation. The nanocomposite of Ag/Pr<SUB>6</SUB>O<SUB>11</SUB>-NRs demonstrated a higher catalytic activity for CO oxidation than Ag/Pr<SUB>6</SUB>O<SUB>11</SUB>-NPs at lower temperatures. This improved performance may be ascribed to the mesoporous features and resultant oxygen vacancies of the Pr<SUB>6</SUB>O<SUB>11</SUB> nanorods support, as well as the large surface area and homogeneous loading of Ag species. As a result, 98.7 and 100% CO conversions were achieved at 210 and 240 °C for Ag/Pr<SUB>6</SUB>O<SUB>11</SUB>-NRs, while Ag/Pr<SUB>6</SUB>O<SUB>11</SUB>-NPs require a temperature of 320 °C to obtain the 100% CO conversion rate. These findings reveal that Pr<SUB>6</SUB>O<SUB>11</SUB>-NRs is the preferable support, comparative to Pr<SUB>6</SUB>O<SUB>11</SUB>-NPs, for Ag/Pr<SUB>6</SUB>O<SUB>11</SUB> catalysts, for CO oxidation.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/iecred/2017/iecred.2017.56.issue-39/acs.iecr.7b02530/production/images/medium/ie-2017-02530c_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ie7b02530'>ACS Electronic Supporting Info</A></P>
ULTRAFINE AU NANODOTS ON GRAPHENE OXIDE FOR CATALYTIC REDUCTION OF 4-NITROPHENOL
JIANLI CHEN,GANG CHENG,ZHUANGNAN LI,FUJUN MIAO,XIAOQIANG CUI,WEITAO ZHENG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2013 NANO Vol.8 No.3
Graphene oxide nanosheet is an ideal platform to capture nanoparticles for highly efficient catalysis, electrochemical sensing and biosensing. In this work, we have described a simple synthesis method for preparation graphene oxide–Au nanohybrid. Au nanodots with an average size of 1.6 nm uniformly dispersed on the surface of graphene oxide. The well-defined nanostructure has been characterized by transmission electron microscopy (TEM) and atomic force microscopy (AFM). The nanohybrid also exhibits enhanced catalytic activity toward the reduction of 4-nitrophenol by NaBH4. Comparing with pure Au nanodots and graphene oxide, graphene oxide–Au nanohybrid shows the highest catalytic activity. This approach not only suggests a wide potential application of graphene oxide nanosheet as a host material for supporting a variety of nanoparticles, but also provides a new approach for the fabrication of graphene-based nanohybrids with multiple physical and chemical properties.