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A Highly Efficient Aeroelastic Optimization Method Based on a Surrogate Model
Zhiqiang, Wan,Xiaozhe, Wang,Chao, Yang The Korean Society for Aeronautical and Space Scie 2016 International Journal of Aeronautical and Space Sc Vol.17 No.4
This paper presents a highly efficient aeroelastic optimization method based on a surrogate model; the model is verified by considering the case of a high-aspect-ratio composite wing. Optimization frameworks using the Kriging model and genetic algorithm (GA), the Kriging model and improved particle swarm optimization (IPSO), and the back propagation neural network model (BP) and IPSO are presented. The feasibility of the method is verified, as the model can improve the optimization efficiency while also satisfying the engineering requirements. Moreover, the effects of the number of design variables and number of constraints on the optimization efficiency and objective function are analysed in detail. The accuracy of two surrogate models in aeroelastic optimization is also compared. The Kriging model is constructed more conveniently, and its predictive accuracy of the aeroelastic responses also satisfies the engineering requirements. According to the case of a high-aspect-ratio composite wing, the GA is better at global optimization.
A Highly Efficient Aeroelastic Optimization Method Based on a Surrogate Model
Wan Zhiqiang,Wang Xiaozhe,Yang Chao 한국항공우주학회 2016 International Journal of Aeronautical and Space Sc Vol.17 No.4
This paper presents a highly efficient aeroelastic optimization method based on a surrogate model; the model is verified by considering the case of a high-aspect-ratio composite wing. Optimization frameworks using the Kriging model and genetic algorithm (GA), the Kriging model and improved particle swarm optimization (IPSO), and the back propagation neural network model (BP) and IPSO are presented. The feasibility of the method is verified, as the model can improve the optimization efficiency while also satisfying the engineering requirements. Moreover, the effects of the number of design variables and number of constraints on the optimization efficiency and objective function are analysed in detail. The accuracy of two surrogate models in aeroelastic optimization is also compared. The Kriging model is constructed more conveniently, and its predictive accuracy of the aeroelastic responses also satisfies the engineering requirements. According to the case of a high-aspect-ratio composite wing, the GA is better at global optimization.
Zhang Zhiqiang,Xiao Chao 한국출판학회 2010 한국출판학연구 Vol.36 No.1
This paper reviews the 11 books of Introduction to Publishing Science which were published in China during the past two decades. From both the macro‐level and the micro‐level, the paper focuses on the similarities and differences of the 11 books. In the meanwhile, on the basis of the current research styles of these books and the present application of theories in other disciplines, the development trends of this kind of books are discussed in the paper.
Zheng, Chao,Zhang, Kai,Sheng, Canhui,Lin, Junjie,Xue, Jinying,Chen, Dezhi,Zhang, Zhiqiang,Luo, Bangyun 대한전기학회 2014 The Journal of International Council on Electrical Vol.4 No.1
Aiming at the three UHVDC controller model in the electromechanical simulation software BPA which widely used in China, the structural features were analyzed. By the time-domain simulation, the influence of different simulation models and the key controller parameters on the recovery characteristics of the receiving end power system were studied. Simulation results show that the commutation failure simulated method impacts the recovery characteristic significantly for weak power grids, increasing the voltage measurement time constant of constant dc power control module and enhancing the start voltage threshold of voltage dependent current order limit (VDCOL) can decrease the reactive power consumption of inverter during the disturbance, and can help to improve the recovery characteristic of receiving end power grid.
Yanmei Feng,Zhiqiang Wang,Yunfeng Yang,Xiang-Feng Wu,Xiaodong Gong,Yajian Liu,Yufei Li,Zuo-Lin Cao,Chao Wang,Xin Tong 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.7
The Ag2SO3/NaNbO3 hybrids have been fabricated via a facile method at room temperature. Several methods such as X-ray diffraction, UV-Vis diffuse reflectance spectroscopy, scanning electron microscopy, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy were used to characterize the samples. Moreover, the photocatalytic activity of the samples was assessed by degradation of rhodamine B and methyl orange under the visible light illumination. Experimental results indicated the photocatalytic degradation efficiency of the as-fabricated hybrids was first increased and then decreased with increasing the dosage of NaNbO3. When the molar ratio of Ag2SO3 to NaNbO3 was 1:0.7, the as-fabricated composites had the best photodegradation efficiency of 96.4% in 30 min for rhodamine B and 97.1% in 60 min for methyl orange, respectively. These were obviously higher than that of pure samples. Furthermore, Ag2SO3 was conjugated with NaNbO3 via chemical-bonds rather than physical contact. In addition, the possible photocatalytic degradation mechanism was also provided and the main roles during the process of photocatalytic degradation were played by holes.
Parallel FM Signal Demodulation System based on Software Radio Platform
Yun Lin,Jiaxing Wang,Chao Lv,Zhiqiang Wu,Qiang Li,Zhiping Zhang 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.3
A parallel FM signal demodulation system is designed in this paper. All FM signals from 90MHz to 110MHz could be captured, separated and restored into original information. The method of digital channelized receiving is used in the system to divide the broadband signals into independent ones according to their center frequency. This design could be used in the field of electron reconnaissance and multichannel communication system. We realized the design on a software radio platform based on the structure of SCA (Software Communication Architecture), and the advantages of this ideal is discussed in the paper.
Influence of synthesis parameters on phase evolution and micromorphology of lanthanum hexaaluminate
Xiaoao Li,Jianjiang Xin,,Chao Chen,Zhiqiang Du,Haotian Wang 한양대학교 세라믹연구소 2022 Journal of Ceramic Processing Research Vol.23 No.2
Lanthanum hexaaluminate is a potential candidate for thermal barrier coatings due to its unique lamellar structure andexcellent thermophysical properties. In this work, lanthanum hexaaluminate was prepared by a solid-state reaction synthesisat 1600 oC, and the effects of aluminum source type and molding method on the phase composition and microstructure of thepowder were studied. It can be seen that the synthesis efficiency of alumina as aluminium source is higher than that ofaluminium hydroxide. However, the flake structure is more obvious when aluminium hydroxide is used to synthesizealuminium hydroxide. In addition, the process of compacting green compact can effectively improve the synthesis efficiencyof LaAl11O18, but it will also affect the formation and growth of grains. Consequently, a high yield of LaAl11O18 powder witha particle size of 3 μm and aspect ratio of 9.88 can be obtained by compacting aluminum hydroxide as the aluminum source.
Guoai He,Cunxiao He,Yu Liu,Chao Liu,Zhiqiang Fu,Shuanghui Xu,Xiaofei Sheng,Zhu Xiao,Qinghong Wen 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.9
Dynamic softening behavior has been of great concern in the aluminum alloys, which served a vital role in affecting themicrostructure, deformation resistance and the final mechanical properties. In this paper, spray deposition was applied tomanufacture AlZnMgCu alloy to refine the casting microstructure and reduce segregation. The microstructure responses andcorresponding mechanism during the thermal compression with various temperatures and various strain rates were multiscalecharacterized and uncovered using high-resolution EBSD. The results revealed that many broken and fine grains wereobserved in the uneven and jagged grain boundaries under the low temperatures and high strain rates, which indicated theoccurrence of partial discontinuous dynamic recrystallization (DDRX). In addition, high density dislocations were formedat original grain boundaries, where great amount of low angle grain boundaries (LAGBs) were appeared. With temperatureincreased and strains rate decreased, the LAGBs would evolve to the high angle grain boundaries (HAGBs) owing to theconsiderable dislocations migrated to the grain boundaries then accumulated, which triggered the occurrence of continuousdynamic recrystallization (CDRX). Two different dynamic recrystallization types were observed and factors that influenceddifferent dynamic recrystallization behaviors were clearly elaborated, and the corresponding mechanism was indicateddetailly.
Occurrence, evolution, and functions of DNA phosphorothioate epigenetics in bacteria
Tong, Tong,Chen, Si,Wang, Lianrong,Tang, You,Ryu, Jae Yong,Jiang, Susu,Wu, Xiaolin,Chen, Chao,Luo, Jie,Deng, Zixin,Li, Zhiqiang,Lee, Sang Yup,Chen, Shi National Academy of Sciences 2018 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.115 No.13
<P><B>Significance</B></P><P>Phosphorothioate (PT) modification of the DNA sugar-phosphate backbone is an important microbial epigenetic modification governed by DndABCDE, which together with DndFGH, constitutes a restriction-modification system. We show that up to 45% of 1,349 identified bacterial <I>dnd</I> systems exhibit the form of solitary <I>dndABCDE</I> without the restriction counterparts of <I>dndFGH</I>. The combination of epigenomics, transcriptome analysis, and metabolomics suggests that in addition to providing a genetic barrier against invasive DNA, PT modification is a versatile player involved in the epigenetic control of gene expression and the maintenance of cellular redox homeostasis. This finding provides evolutionary and functional insights into this unusual epigenetic modification. Our results imply that PT systems might evolve similar to other epigenetic modification systems with multiple cellular functions.</P><P>The chemical diversity of physiological DNA modifications has expanded with the identification of phosphorothioate (PT) modification in which the nonbridging oxygen in the sugar-phosphate backbone of DNA is replaced by sulfur. Together with DndFGH as cognate restriction enzymes, DNA PT modification, which is catalyzed by the DndABCDE proteins, functions as a bacterial restriction-modification (R-M) system that protects cells against invading foreign DNA. However, the occurrence of <I>dnd</I> systems across a large number of bacterial genomes and their functions other than R-M are poorly understood. Here, a genomic survey revealed the prevalence of bacterial <I>dnd</I> systems: 1,349 bacterial <I>dnd</I> systems were observed to occur sporadically across diverse phylogenetic groups, and nearly half of these occur in the form of a solitary <I>dndBCDE</I> gene cluster that lacks the <I>dndFGH</I> restriction counterparts. A phylogenetic analysis of 734 complete PT R-M pairs revealed the coevolution of M and R components, despite the observation that several PT R-M pairs appeared to be assembled from M and R parts acquired from distantly related organisms. Concurrent epigenomic analysis, transcriptome analysis, and metabolome characterization showed that a solitary PT modification contributed to the overall cellular redox state, the loss of which perturbed the cellular redox balance and induced <I>Pseudomonas fluorescens</I> to reconfigure its metabolism to fend off oxidative stress. An in vitro transcriptional assay revealed altered transcriptional efficiency in the presence of PT DNA modification, implicating its function in epigenetic regulation. These data suggest the versatility of PT in addition to its involvement in R-M protection.</P>