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An optimization model of parameter matching for aircraft catapult launch

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Chinese Journal of Aeronautics 2020年第1期33卷 191-204页

作者： zeyang zhou Jun HUANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China

To efficiently and fully utilize aircraft carrier resources,an optimization model is presented to deal with parameter matching between aircraft and carrier in the process of aircraft catapult *** on carrier aircraft longitudinal dynamic equations and theorem of kinetic energy in catapult launch course,the work characteristics of different forces are learned and a theory model of parameter matching is *** view of the uncertainty of the model parameters of the theory model and the low matching accuracy of the approximate model,an optimization model of parameter matching is introduced in line with the structure of theory model and the approximate model and is generated by the proposed immune genetic *** with the original genetic algorithm and immune algorithm,the proposed algorithm has better calculation accuracy and *** calculation results show that the optimization model occupies certain application value of engineering estimation from the comparison with the relevant literature data and has higher precision than the approximate *** validity of the proposed approach is verified with numerical case study on a carrier based aircraft.

关键词： Aircraft catapult launch Approximate model Immune genetic algorithm Optimization model Parameter matching Theory model

Electromagnetic scattering characteristics of coaxial helicopter based on dynamic transformation method

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Chinese Journal of Aeronautics 2021年第2期34卷 516-528页

作者： zeyang zhou Jun HUANG Jinjun WANG School of Aeronautic Science and Engineering Beihcmg UniversityBeijing 100083China

With the development of coaxial rotors and high-speed helicopters, the electromagnetic scattering characteristics of coaxial helicopters have gradually become a research hotspot. In order to deal with the Radar Cross-Section(RCS) of high-speed rotating rotors or coaxial main rotors, a Dynamic Scattering Method(DSM) based on dynamic process simulation and grid coordinate transformation is presented. Instantaneous electromagnetic scattering from rotors and helicopters is solved using Physical Optics(PO) and Physical Theory of Diffraction(PTD). Important factors are analyzed and discussed in detail, including individual rotor rotation, azimuth, elevation angle,fuselage, pitch angle, and roll angle. The results show that the electromagnetic scattering characteristics of rotor-type components are dynamic and periodic. The dynamic RCS period of a single rotor is related to the dynamic RCS period of the coaxial main rotor. Choosing different observation angles and attitude angles has a great impact on the static and dynamic RCS of the *** presented DSM is effective and efficient to analyze and determine the dynamic electromagnetic scattering characteristics of conventional helicopters or coaxial helicopters.

关键词： Coaxial helicopter Dynamic electromagnetic scattering Radar cross section Radar stealth Rotor

Linear random search and engineering estimation of sinkage for launching carrier aircraft

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Science China(Technological Sciences) 2019年第6期62卷 996-1002页

作者： ZHONG Guo HUANG Jun zhou zeyang YI MingXu School of Aeronautic Science and Engineering Beijing University of Aeronautics and Astronautics

A linear random search algorithm(LRSA) is developed to determine the critical value of takeoff weight limited to the safe flight track sinkage and an engineering estimation method(EEM) is proposed to calculate the sinkage of carrier aircraft launch in real time. Based on the analysis of free flight after leaving the carrier, the equations are established to participate into engineering estimation of flight track sinkage. Thanks to the proposed search algorithm, the maximum takeoff weight of carrier aircraft with safe catapult launch flight track sinkage is generated in few steps. The results of sinkage estimation and the search algorithm are in good agreement with that of aircraft catapult launch simulation. The main contribution of this manuscript is the establishment of simple and accurate engineering estimation for carrier aircraft launch flight track sinkage and the development of robust and efficient search algorithm for the critical value with safe catapult criteria.

关键词： carrier aircraft launch flight track sinkage engineering estimation linear random search simulation

Soil seismic analysis for 2D oblique incident waves using exact free-field responses by frequency-based finite/infinite element method

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Frontiers of Structural and Civil Engineering 2022年第12期16卷 1530-1551页

作者： Yeong-Bin Yang zeyang zhou Xiongfei Zhang Xiaoli Wang School of Civil Engineering Chongqing UniversityChongqing 400045China MOE Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing 400045China School of Civil Engineering and Architecture Chongqing University of Science and TechnologyChongqing 400045China

The seismic analysis of a viscoelastic half-space under two-dimensional(2D)oblique incident waves is carried out by the finite/infinite element method(FIEM).First,the frequency-domain exact solutions for the displacements and stresses of the free field are derived in general form for arbitrary incident P and SV *** the present formulation,no distinction needs to be made for SV waves with over-critical incident angles that make the reflected P waves disappear,while no critical angle exists for P ***,the equivalent seismic forces of the earthquake(Taft Earthquake 1952)imposed on the near-field boundary are generated by combining the solutions for unit ground accelerations with the earthquake *** on the asymmetric finite/infinite element model,the frequency-domain motion equations for seismic analysis are presented with the key parameters *** results obtained in frequency and time domain are verified against those of Wolf’s,Luco and de Barros’and for inversely computed ground *** parametric study indicated that distinct phase difference exists between the horizontal and vertical responses for SV waves with over-critical incident angles,but not for under-critical incident *** observations were also made for the numerical results inside the text.

关键词： oblique incident waves critical angle half-space finite/infinite element approach seismic response analysis

2.5-dimension soil seismic response to oblique incident waves based on exact free-field solution

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 216-235页

作者： Yeongbin Yang zeyang zhou Xiaoli Wang Xiongfei Zhang Zhilu Wang School of Civil Engineering Chongqing UniversityChongqing 400045China School of Civil Engineering and Architecture Chongqing University of Science and TechnologyChongqing 401331China

With the three dimensional(3D)oblique incident waves exactly determined for the free field,the soil seismic responses in both frequency and time domains are studied by the 2.5 dimension(2.5D)finite/infinite element ***,the free-field responses in frequency domain are solved exactly for 3D arbitrary incident P and SV waves,which requires no coordinate conversion or extra effort for SV waves with super-critical incident ***,the earthquake spectra are incorporated by the concept of equivalent seismic forces on the near-field boundary,based only on the displacements input derived for unit ground accelerations of each frequency using the 2.5D *** the asymmetric 2.5D finite/infinite element model adopted,the procedure for soil seismic analysis is *** solutions computed by the proposed method are verified against those of Wolf’s and de Barros and Luco’s and for inversely calculated ground *** interest is that abrupt variation in soil response occurs around the critical angle on the wave propagation plane for SV *** addition,the horizontal displacements attenuate with increasing horizontal incident angle,while the longitudinal ones increase inversely for 3D incident P and SV waves.

关键词： 3D oblique incident wave seismic response analysis 2.5D approach infinite element half-space

Seismic analysis of underground tunnels subjected to 3D oblique incident P and SV waves by 2.5D approach

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Underground Space 2023年第5期12卷 271-286页

作者： Yeong-Bin Yang Xiaoli Wang zeyang zhou Xiongfei Zhang Zhi Li School of Civil Engineering Chongqing UniversityChongqing 400045China School of Civil Engineering and Architecture Chongqing University of Science and TechnologyChongqing 401331China

This paper presents,for the first time,the consideration of three-dimensional(3D)oblique incident P and SV waves in calculating the 3D seismic response of a lined tunnel embedded in a half-space by the 2.5D finite/infinite element method(FIEM).Firstly,the applicability of the 2.5D FIEM for 3D seismic analysis is *** the exact solutions obtained for the free field in the Appendix,the equivalent seismic forces are rationally computed for the near-field boundary,considering the horizontal and vertical excitations of the Chi-Chi *** performing seismic analysis of the half space embedded with a tunnel using the 2.5D FIEM,the time-domain responses of the tunnel are *** accuracy of the present solutions is verified against those of de Barros and *** drawn from the parametric study include:(1)Stress concentration for the principal stress under oblique incident seismic waves occurs at the polar angles of 0(vault),90,180(inverted arch),and 270of the lining wall.(2)The vault and inverted arch are the weakest parts of the tunnel during earthquakes.(3)The accelerations of the tunnel during earthquakes can be regarded as of the rigid body type.(4)The responses of the tunnel lining caused by SV waves of an earthquake are much more critical than those by P waves.(5)For arbitrary seismic waves,the maximum longitudinal acceleration azmax is of the same order of magnitude as the maximum horizontal acceleration axmax.

关键词： Earthquake Finite/infinite element method 3D oblique incident waves Time domain response Tunnel 2.5D approach

BmSE, a SINE family with 3′ ends of (ATTT) repeats in domesticated silkworm (Bombyx mori)

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Journal of Genetics and Genomics 2010年第2期37卷 125-135页

作者： Jinshan Xu Tie Liu Dong Li Ze Zhang Qinyou Xia zeyang zhou Laboratory of Animal Biology Chongqing Normal University Chongqing 400047 China Engineering Research Center of Bioactive Substances Chongqing Normal University Chongqing 400047 China Institute of Sericulture and System Biology Southwest University Chongqing 400716 China

Short interspersed elements （SINEs）, which are mainly composed of Bm1, are abundant in the domesticated silkworm. A 294 bp novel SINE family, designated as BmSE, was identified by mining the database of the complete Bombyx mori genome. A representational BmSE element is flanked by an 11 bp target site duplication sequence posterior poly （A） at the 3′ end and has the sequence motifs of an internal promoter of RNA polymerase III, which are similar to that of Bm1. The repetitive elements of BmSE are widely distributed in all 28 chromosomes of the genome and share the common （ATTT） repeats at the ends. GC-content distribution shows that BmSE tends to accumulate preferably in the region of higher AT content than that of Bm1. A high proportion of the BmSEs are mapped to the coding sequence introns, whereas several elements are also present in the UTR of some transcripts, indicating that BmSEs are indeed exonized with UTRs. Of the 615 identified structural variants （SVs） of BmSE among the 40 domesticated and wild silkworms, only 230 SVs were found in the domesticated silkworms, indicating that many recent SV events of BmSE occurred after domestication, which was probably due to its mobilization. Our analysis might assist in developing BmSE as a potential marker and in understanding the evolutionary roles of SINEs in the domesticated silkworm.

关键词： domesticated silkworm SINE distribution structural variant

Analysis of cytochrome P450 genes in silkworm genome (Bombyx mori)

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Science China(Life Sciences) 2005年第4期48卷 414-418页

作者： LI Bin XIA Qingyou LU Cheng zhou zeyang XIANG Zhonghuai Key Sericultural Laboratory of Agricultural Ministry College of Sericulture&BiotechnologySouthwest Agricultural UniversityChongqing 400716China

We have searched the Bombyx mori genome for members of the major enzyme family,the Cytochrome P450s,which carry out multiple reactions to enable organisms to rid themselves of foreign *** a result,86 putative P450s were discovered in silkworm genome,which are thought to belong to 32 subfamilies.A comparative genomic analysis with Drosophila melanogaster reveals that the two insects have some similar P450 distribution pat-terns but still have some obvious ***,the diverse distribution exists in 7 p450 subfamilies,which are CYP4A,CYP4C,CYP4D,CYP6A,CYP6AE,CYP6B and ***-thermore,we collected expression sequence tag(EST)evidence for 49 putative P450s genes,which are expressed at the transcriptional level and more likely to be true P450s.

关键词： cytochrome P450 silkworm genome.

Mitochondrial pyruvate dehydrogenase E1 of Nosema bombycis:A marker in Microsporidian evolution

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Current Zoology 2009年第6期55卷 423-429页

作者： Tian LI Xiaoqun DANG Jinshan XU Handeng LIU Guoqing PAN zeyang zhou The Key Sericultural Laboratory of Agricultural Ministry Southwest University Chongqing 400716 China Laboratory of Animal Biology Chongqing Normal University Chongqing 400047 China

Microsporidia are a group of intracelluar eukaryotic parasites, which can infected almost all animals, including human beings. Till now, no mitochodria but mitosome, a remnant of mitochondria was discovered in this phylum. We present here the mitochondrial pyruvate dehydrogenase El （PDH, including PDHα and PDHβ） of the microsporidian Nosema bombycis, the pathogen of silkworm pebrine. Compared with PDH of microsporidian Encephalitozoon cuniculi and Antonospora locustae, both subunits are eonscrced. The phylogeny indicated that both subunits are mitochondrial. The syntenic maps revealed the subunits organization of NbPDH is distributed in different scaffolds, similar to that of EcPDH but different with AIPDH, and the relationship between phylogeny tree and organization of PDH suggest that the AlPDH subunits organization is the ancestral style of microsporidia, and through the genome evolution, the reshuffling of the chromosome of microsporidia occurred, the adjacent style of ALPDHE1 organization changed, and the two subunits separated and located to different chromosomes in E. cuniculi. For N. bombycis and N. ceranae, they locate to different scaffolds. In order to determine NbPDH subcellular localizations, we prepared the polyclonal antibodies against NbPDH prokaryotic fusion proteins, and adopted the colloidal gold immunological electron microscopy, the expression signals of NbPDH were observed in spores however, the subcellular localization were not definited. In general, through comparison of three mierosporidian PDH molecular phylogeny, subunits organization in chromosomes, localization indicated that PDH is an interesting marker in microsporidia evolution

关键词： Microsporidia Nosema bombycis PDH Synteny Immunoloealization Evolution