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Development and formation of wing cuticle based on transcriptomic analysis in Locusta migratoria during metamorphosis
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作者 Jing Zhang Zhaochen Wu +5 位作者 Shuo Li He Huang Suning Liu Weimin Liu Xiaoming Zhao Jianzhen Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1285-1299,共15页
Wings are an important flight organ of insects.Wing development is a complex process controlled by a series of genes.The flightless wing pad transforms into a mature wing with the function of migratory flight during t... Wings are an important flight organ of insects.Wing development is a complex process controlled by a series of genes.The flightless wing pad transforms into a mature wing with the function of migratory flight during the nymphto-adult metamorphosis.However,the mechanism of wing morphogenesis in locusts is still unclear.This study analyzed the microstructures of the locust wing pads at pre-eclosion and the wings after eclosion and performed the comparative transcriptome analysis.RNA-seq identified 25,334 unigenesand 3,430 differentially expressed genes(DEGs)(1,907 up-regulated and 1,523 down-regulated).The DEGs mainly included cuticle development(LmACPs),chitin metabolism(Lm Idgf4),lipid metabolism-related genes,cell adhesion(Integrin),zinc finger transcription factors(LmSalm,LmZF593 andLmZF521),and others.Functional analysis based on RNA interference and hematoxylin and eosin(H&E)staining showed that the three genes encoded zinc finger transcription factors are essential for forming wing cuticle and maintaining morphology in Locusta migratoria.Finally,the study found that the LmSalm regulates the expression of LmACPs in the wing pads at pre-eclosion,and LmZF593 and LmZF521 regulate the expression of LmIntegrin/LmIdgf4/LmHMT420 in the wings after eclosion.This study revealed that the molecular regulatory axis controls wing morphology in nymphal and adult stages of locusts,offering a theoretical basis for the study of wing development mechanisms in hemimetabolous insects. 展开更多
关键词 Locusta migratoria wing development METAMORPHOSIS RNA-SEQ
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Numerical Investigations on Dynamic Stall Characteristics of a Finite Wing
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作者 JING Simeng CAO Chenkai +2 位作者 GAO Yuan ZHAO Qijun ZHAO Guoqing 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期444-457,共14页
The paper examines the dynamic stall characteristics of a finite wing with an aspect ratio of eight in order to explore the 3D effects on flow topology,aerodynamic characteristics,and pitching damping.Firstly,CFD meth... The paper examines the dynamic stall characteristics of a finite wing with an aspect ratio of eight in order to explore the 3D effects on flow topology,aerodynamic characteristics,and pitching damping.Firstly,CFD methods are developed to calculate the aerodynamic characteristics of wings.The URANS equations are solved using a finite volume method,and the two-equation k-ωshear stress transport(SST)turbulence model is employed to account for viscosity effects.Secondly,the CFD methods are used to simulate the aerodynamic characteristics of both a static,rectangular wing and a pitching,tapered wing to verify their effectiveness and accuracy.The numerical results show good agreement with experimental data.Subsequently,the static and dynamic characteristics of the finite wing are computed and discussed.The results reveal significant 3D flow structures during both static and dynamic stalls,including wing tip vortices,arch vortices,Ω-type vortices,and ring vortices.These phenomena lead to differences in the aerodynamic characteristics of the finite wing compared with a 2D airfoil.Specifically,the finite wing has a smaller lift slope during attached-flow stages,higher stall angles,and more gradual stall behavior.Flow separation initially occurs in the middle spanwise section and gradually spreads to both ends.Regarding aerodynamic damping,the inboard sections mainly generate unstable loading.Furthermore,sections experiencing light stall have a higher tendency to produce negative damping compared with sections experiencing deep dynamic stall. 展开更多
关键词 finite wing dynamic stall aerodynamic damping 3D effects
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An adaptive machine learning-based optimization method in the aerodynamic analysis of a finite wing under various cruise conditions
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作者 Zilan Zhang Yu Ao +1 位作者 Shaofan Li Grace X.Gu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第1期27-34,共8页
Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight missions.Plenty of existing literature has considered two-dimensional infinite airfoil... Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight missions.Plenty of existing literature has considered two-dimensional infinite airfoil optimization,while three-dimensional finite wing optimizations are subject to limited study because of high computational costs.Here we create an adaptive optimization methodology built upon digitized wing shape deformation and deep learning algorithms,which enable the rapid formulation of finite wing designs for specific aerodynamic performance demands under different cruise conditions.This methodology unfolds in three stages:radial basis function interpolated wing generation,collection of inputs from computational fluid dynamics simulations,and deep neural network that constructs the surrogate model for the optimal wing configuration.It has been demonstrated that the proposed methodology can significantly reduce the computational cost of numerical simulations.It also has the potential to optimize various aerial vehicles undergoing different mission environments,loading conditions,and safety requirements. 展开更多
关键词 Aerodynamic optimization Computational fluid dynamics Radial basis function Finite wing Deep learning neural network
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南方山地WiNG节点排列高效QC方法
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作者 黄国华 申志恩 +2 位作者 马志虎 尹思奇 张庆元 《物探装备》 2024年第5期322-326,共5页
XCN三维是首个使用WiNG节点的山地物探项目,为了掌握WiNG仪器的Pathfinder、点对点等QC方式在山地使用的性能特点,提高仪器生产效率,首先在工区中选择具有代表性的试验点,使用小排列进行Pathfinder、点对点等QC方式试验,总结出初步的WiN... XCN三维是首个使用WiNG节点的山地物探项目,为了掌握WiNG仪器的Pathfinder、点对点等QC方式在山地使用的性能特点,提高仪器生产效率,首先在工区中选择具有代表性的试验点,使用小排列进行Pathfinder、点对点等QC方式试验,总结出初步的WiNG节点排列山地QC方法。然后在项目大规模WiNG节点排列的QC过程中不断总结纠正,找出山地WiNG节点大排列QC方法的使用特点,从而总结出一套适合南方山地的WiNG节点排列的高效QC方法,达到山地WiNG仪器生产提速、提效、提质的目的。 展开更多
关键词 南方山地 wing PATHFINDER QC
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Thrust Optimization of Flapping Wing via Gradient Descent Technologies
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作者 Jeshwanth Kundem 《Open Journal of Fluid Dynamics》 2024年第2期83-99,共17页
The current work aims at employing a gradient descent algorithm for optimizing the thrust of a flapping wing. An in-house solver has been employed, along with mesh movement methodologies to capture the dynamics of flo... The current work aims at employing a gradient descent algorithm for optimizing the thrust of a flapping wing. An in-house solver has been employed, along with mesh movement methodologies to capture the dynamics of flow around the airfoil. An efficient framework for implementing the coupled solver and optimization in a multicore environment has been implemented for the generation of optimized solutionsmaximizing thrust performance & computational speed. 展开更多
关键词 Steepest Descent CFD Flapping wing Airfoil Thrust Performance
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Wings-FDY一步法生产ITY的工艺研究
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作者 周龙 余锡攀 +2 位作者 李振宇 孙建杰 杜杨洋 《聚酯工业》 CAS 2024年第3期26-28,共3页
通过设备改造及工艺优化,成功实现了ITY在Wings-FDY设备上一步法生产。研究结果表明:风压设定为30 Pa,调整纺丝/卷绕上油比例为6:4,预热辊温度51℃,定型辊温度124℃,拉伸倍数3.2,卷绕速度3550 m/min时,ITY 148dtex/108f纺况稳定,物理指... 通过设备改造及工艺优化,成功实现了ITY在Wings-FDY设备上一步法生产。研究结果表明:风压设定为30 Pa,调整纺丝/卷绕上油比例为6:4,预热辊温度51℃,定型辊温度124℃,拉伸倍数3.2,卷绕速度3550 m/min时,ITY 148dtex/108f纺况稳定,物理指标均匀,满足客户定制化的产品需求。 展开更多
关键词 ITY wings-FDY 设备改造
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WingsFDY设备生产22dtex/24f细旦涤纶的工艺探讨
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作者 翟佳羽 袁礼栋 +2 位作者 李婧楠 苏宏新 赵毛毛 《合成纤维》 CAS 2024年第8期18-22,共5页
对22dtex/24f细旦涤纶全拉伸丝(FDY)生产中的熔体输送工艺、纺丝工艺、冷却工艺和牵伸定形等工艺进行了详细的分析与探讨。生产实践表明,该产品生产中采用的巴马格8辊WingsFDY设备具有高效节能、流程短的优势,能够有效降低FDY的生产成本... 对22dtex/24f细旦涤纶全拉伸丝(FDY)生产中的熔体输送工艺、纺丝工艺、冷却工艺和牵伸定形等工艺进行了详细的分析与探讨。生产实践表明,该产品生产中采用的巴马格8辊WingsFDY设备具有高效节能、流程短的优势,能够有效降低FDY的生产成本,对设备应用及新品种的开发具有一定的实践指导意义。 展开更多
关键词 细旦涤纶DTY 巴马格wingsFDY设备 工艺
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Relevance of zero lift drag coefficient and lift coefficient to Mach number for large aspect ratio winged rigid body
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作者 董素荣 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第3期270-274,共5页
Synthetic analysis is conducted to the wind tunnel experiment results of zero lift drag coefficient and lift coefficient for large aspect ratio winged rigid body.By means of wind tunnel experiment data,the dynamics mo... Synthetic analysis is conducted to the wind tunnel experiment results of zero lift drag coefficient and lift coefficient for large aspect ratio winged rigid body.By means of wind tunnel experiment data,the dynamics model of the zero lift drag coefficient and lift coefficient for the large aspect ratio winged rigid body is amended.The research indicates that the change trends of zero lift drag coefficient and lift coefficient to Mach number are similar.The calculation result and wind tunnel experiment data all verify the validity of the amended dynamics model by which to estimate the zero lift drag coefficient and lift coefficient for the large aspect ratio winged rigid body,and thus providing some technical reference to aerodynamics character analysis of the same types of winged rigid body. 展开更多
关键词 winged rigid body zero lift drag coefficient lift coefficient wind tunnel experiment dynamic characteristics
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Fossil-Winged Fruits of Fraxinus(Oleaceae) and Liriodendron(Magnoliaceae) from the Duho Formation,Pohang Basin,Korea 被引量:3
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作者 Seung-Ho JUNG Seong-Joo LEE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第5期845-852,共8页
A total of 16 specimens of fossil-winged fruits were found from the Middle Miocene marine deposits, Duho Formation, Pohang Basin, Korea. They were identified into two structurally different groups: 15 specimens into ... A total of 16 specimens of fossil-winged fruits were found from the Middle Miocene marine deposits, Duho Formation, Pohang Basin, Korea. They were identified into two structurally different groups: 15 specimens into a winged fruit of Fraxinus, and one specimen of Liriodendron. The most samaras (13 specimens) were identified as Fraxinus oishii, which is characterized by narrowly ovate or ovate-elliptic shapes that are 2.7-3.6 cm in length and 0.7-1 cm in width (i/w ratio=3.4-4). The apexes of the Fraxinus oishii samara are round or slightly emarginated, and a seed of the samara is always located at the base, of which the general shape is narrow rhombic-ellipsoidal. The seed is 1.2-2 cm long and 0.5-0.7 cm wide. Two specimens are different from the samara of Fraxinus oishii. They have a 6.6 length/width ratio (3.3 cm long and 0.5 cm wide), and thus, are temporarily classified into the Fraxinus sp. One specimen was recognized as a winged seed of Liriodendron meisenense. The wing is broadly lanceolate to elliptic in shape, has a smooth, acute apex, and is approximately 3 cm long and 0.7 cm wide. Samaras of Fraxinus oishii and Liriodendron meisenense were early reported from the Middle Miocene deposits from North Korea, but these specimens are the first discovery in South Korea. Further study of the Duho Formation may connect flora relationships between North and South Korea. 展开更多
关键词 winged fruits FRAXINUS LIRIODENDRON Middle Miocene Pohang Basin Korea
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Molecular genetic diversity of winged bean gene pool in Thailand assessed by SSR markers 被引量:1
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作者 Kularb Laosatit Kitiya Amkul +1 位作者 Sompong Chankaew Prakit Somta 《Horticultural Plant Journal》 SCIE CSCD 2022年第1期81-88,共8页
Winged bean[Psophocarpus tetragonolobus(L.)DC.]is a vegetable legume crop.The center of origin,diversity and domestication of this crop are not known.In this study,we assessed the genetic diversity and population stru... Winged bean[Psophocarpus tetragonolobus(L.)DC.]is a vegetable legume crop.The center of origin,diversity and domestication of this crop are not known.In this study,we assessed the genetic diversity and population structure of 457 accessions of winged bean collected from six geographical regions(North,Northeast,East,West,and central,and South)in Thailand using 14 simple sequence repeat(SSR)markers.In total,the SSR markers detected only 55 alleles with an average of 3.9 alleles per locus.Observed heterozygosity was relatively high(0.15)and overall gene diversity was moderate(0.487).Gene diversity,allelic richness and observed heterozygosity in the six regions were comparable,while the estimated out-crossing rate was relatively high(16.4%).STRUCTURE analysis grouped the 457 winged bean accessions into three subpopulations.Neighbor-joining(NJ)analysis grouped all the accessions into two major clusters.Genetic groups identified by both STRUCTURE analysis and NJ analysis were unrelated to geographical origins.Principal coordinate analysis revealed no clear clustering of the winged bean accessions.Although genetic groups were not unrelated to geographical origins,most of the winged bean accessions with long pods(30 cm or higher in length)or having purple seed coats or purple young pods were grouped together.This suggested that the winged beans with long pods or with purple seed or purple young pods may have a single origin.Altogether,these results demonstrated that the genetic diversity of winged bean in Thailand was moderate with high genetic admixture.We argue that the high genetic admixture of the winged bean in Thailand is due to seed migration and relatively high outcrossing rate. 展开更多
关键词 winged bean Psophocarpus tetragonolobus Underutilized crop DIVERSITY Population structure SSR
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Dispersal and germination of winged seeds of Brandisia hancei,a shrub in karst regions of China
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作者 Yongquan Ren Chengling Huang +2 位作者 Jiaming Zhang Yongpeng Ma Xiaoling Tian 《Plant Diversity》 SCIE CAS CSCD 2021年第3期234-238,共5页
Brandisia hancei(Paulowniaceae)is a widely distributed shrub in karst regions in southwestern China.Its seeds have a membranous wing,and they mature just before the rainy season begins.To assess the effect of the wing... Brandisia hancei(Paulowniaceae)is a widely distributed shrub in karst regions in southwestern China.Its seeds have a membranous wing,and they mature just before the rainy season begins.To assess the effect of the wing on seed dispersal and germination of B.hancei,we measured the dispersal distance at varying wind speeds and release heights,falling duration from different release heights,floating duration on still water,rates of imbibition of water,and drying and soil adherence to seeds.Germination experiments were conducted on intact and de-winged seeds immediately after harvest.The wing increased the falling duration in still air and the floating ability on water.Dispersal distance of winged and de-winged seeds did not differ at a wind speed of 2.8 m s1,but at 3.6 and 4.0 m s1 dispersal distances were greater for de-winged than for winged seeds.Seed wing had little effect of absorption and retention of water,but significantly increased soil adherence to the seeds.Mature seeds were non-dormant and germinated to over 90%with a mean germination time of about 10 days.By combining the environmental conditions in karst habitat with the seed traits of B.hancei,we conclude that dispersal and germination of winged seeds are adapted to the precipitation seasonality in heterogeneous habitats absence of soil. 展开更多
关键词 ANEMOCHORY HYDROCHORY Membranous wing Seed dispersal winged seed
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Structural design and modal behaviors analysis of a new swept baffled inflatable wing 被引量:1
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作者 Nuo Ma Li Liu +1 位作者 Fanmin Meng Junhui Meng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期382-398,共17页
Inflatable wing has significant application value in the design of loitering munitions because of its advantages such as lightweight and foldability.However,due to the flexible characteristics,aeroelastic behaviors of... Inflatable wing has significant application value in the design of loitering munitions because of its advantages such as lightweight and foldability.However,due to the flexible characteristics,aeroelastic behaviors of inflatable wings such as flutter are nonnegligible in flight.By designing a certain angle between the inflatable beam and the wing span,the structural dynamic and even the aeroelastic performance of the inflatable wing can be effectively improved.Based on the analysis of the mechanical and geometric characteristics of the inflatable structure,a new inflatable wing with sweep arranged inflatable beams is proposed,and the main design variables and methods are analyzed.For purpose of investigating the aeroelastic performance of the swept baffled inflatable wing,the modal behaviors by considering the wet mode are studied.In consideration of the deficiencies of the traditional wet modal analysis method,by introducing the influence on the additional stiffness of flow field,an added massstiffness method is proposed in this paper,and the advantages are verified by ground vibration experiments.On this basis,the effects of baffles sweep angle,pressure,and boundary conditions on the modal parameters and aeroelastic performance of inflatable wing are analyzed.The results show that the aeroelastic performance of the inflatable wing can be designed by changing the baffles sweep angle,which is enlightened for the aeroelastic tailoring design on inflatable wings. 展开更多
关键词 Inflatable wing Structural design Wet mode Flutter analysis
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Biometrics and wing molt in White-winged Black Tern (Chlidonias leucopterus) in north-west Australia
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作者 Peter J. FULLAGAR Michael J. DAWKINS Clive D. T. MINTON 《Chinese Birds》 CSCD 2013年第4期306-313,共8页
We analyze morphometrics from a sample of 276 White-winged Black Tern(Chlidonias leucopterus) caught in north-west Australia on 4 March 2011. An estimated 40000 terns were present — the largest concentration of this ... We analyze morphometrics from a sample of 276 White-winged Black Tern(Chlidonias leucopterus) caught in north-west Australia on 4 March 2011. An estimated 40000 terns were present — the largest concentration of this species yet reported from Australia. When comparing juveniles with adults, only wing length and body mass differed significantly; however, juveniles were still easily recognized by plumage and wing molt as late as March. There was little evidence of any dramatic weight gain in adults before their northward migration. No morphological characteristic distinguishing sex was found. We confirmed that terns caught in this study did not appear to differ morphologically from those of the western palearctic populations. We describe wing molt based on data from 354 individuals captured and banded in Australia over 28 years. Wing molt proceeds in much the same way as found in other small terns. 展开更多
关键词 White-winged Black Tern morphometrics wing molt AUSTRALIA feeding ROOSTING
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Egg rejection behavior does not explain the lack of cowbird parasitism on an eastern North American population of Red-winged Blackbirds 被引量:1
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作者 Justin J.Reel Todd J.Underwood 《Avian Research》 CSCD 2019年第4期431-440,共10页
Background:Red-winged Blackbirds(Agelaius phoeniceus),hereafter red-wings,are much less frequently parasitized by Brown-headed Cowbirds(Molothrus ater)in eastern North America than in central North America and had not... Background:Red-winged Blackbirds(Agelaius phoeniceus),hereafter red-wings,are much less frequently parasitized by Brown-headed Cowbirds(Molothrus ater)in eastern North America than in central North America and had not been recorded as hosts in our study area in southeastern Pennsylvania.Although hosts of Old World cuckoos(Cuculidae)often show geographic variation in egg rejection behavior,cowbird hosts typically exhibit uniform responses of all acceptance or all rejection of cowbird eggs.Thus,geographic variation in cowbird parasitism frequencies might reflect a different behavioral response to parasitism by hosts where only some populations reject parasitism.In this study,we tested whether egg rejection behavior may explain the lack of parasitism observed in our eastern red-wing population,which may provide insight into low parasitism levels across eastern North America.Methods:We parasitized red-wing nests with model cowbird eggs to determine their response to parasitism.Nests were tested across three nest stages and compared to control nests with no manipulations.Because rejection differed significantly by stage,we compared responses separately for each nest stage.We also monitored other songbird nests to identify parasitism frequencies on all potential hosts.Results:Red-wings showed significantly more rejections during the building stage,but not for the laying and incubation stages.Rejections during nest building involved mostly egg burials,which likely represent a continuation of the nest building process rather than true rejection of the cowbird egg.Excluding these responses,red-wings rejected 15%of cowbird eggs,which is similar to rejection levels from other studies and populations.The overall parasitism frequency on 11 species surveyed in our study area was only 7.4%.Conclusions:Egg rejection behavior does not explain the lack of parasitism on red-wings in our eastern population.Alternatively,we suggest that cowbird preference for other hosts and the low abundance of cowbirds in the east might explain the lack of parasitism.Future research should also explore cowbird and host density and the makeup of the host community to explain the low levels of parasitism on red-wings across eastern North America because egg rejection alone is unlikely to explain this broad geographic trend. 展开更多
关键词 Brood parasitism Brown-headed Cowbird Egg rejection Geographic variation Red-winged Blackbird
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GOLD AND SILVER WINGED GODS FROM THE TUBO PERIOD 被引量:1
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作者 Huo Wei 《China's Tibet》 2018年第1期54-57,共4页
Ethnic people living on the Tibetan Plateau during the Tubo period have been well-known as not only strong and brave on horses,but they were also an ethnic group enriched with powerful creativity and rich imagination.... Ethnic people living on the Tibetan Plateau during the Tubo period have been well-known as not only strong and brave on horses,but they were also an ethnic group enriched with powerful creativity and rich imagination.From Tubo’s cultural art,we can observe a large amount of extremely fine artifacts.For instance,among 展开更多
关键词 GOLD AND SILVER winged GODS FROM THE TUBO PERIOD
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Quantitative analysis of the morphing wing mechanism of raptors:Morphing kinematics of Falco peregrinus wing
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作者 唐迪 车婧琦 +4 位作者 金伟杰 崔亚辉 范忠勇 杨茵 刘大伟 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期68-77,共10页
Raptors are getting more attention from researchers because of their excellent flight abilities.And the excellent wing morphing ability is critical for raptors to achieve high maneuvering flight,which can be a good bi... Raptors are getting more attention from researchers because of their excellent flight abilities.And the excellent wing morphing ability is critical for raptors to achieve high maneuvering flight,which can be a good bionic inspiration for unmanned aerial vehicles(UAV)design.However,morphing wing motions of Falco peregrinus with multi postures cannot be consulted since such a motion database was nonexistent.This study aimed to provide data reference for future research in wing morphing kinetics.We used the computed tomography(CT)approach to obtain nine critical postures of the Falco peregrinus wing skeleton,followed with motion analysis of each joint and bone.Based on the obtained motion database,a six-bar kinematic model was proposed to regenerate wing motions with a high fidelity. 展开更多
关键词 RAPTOR wing morphing skeletal mechanism CT scans six-bar model
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Wings-plus设备生产全消光FDY工艺探讨 被引量:1
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作者 冯斌 朱昌波 +3 位作者 褚冬生 郑伟 唐晓凯 崔利 《聚酯工业》 CAS 2023年第4期45-47,共3页
在大容量聚酯熔体直纺生产线上进行设备技术改造,在熔体输送管道上通过在线添加注射设备将全消光母粒注射进入熔体,并在动态混合器中混合均匀,得到全消光聚酯熔体,采用巴马格的Wings-plus FDY生产设备的一步拉伸工艺生产全消光FDY纤维... 在大容量聚酯熔体直纺生产线上进行设备技术改造,在熔体输送管道上通过在线添加注射设备将全消光母粒注射进入熔体,并在动态混合器中混合均匀,得到全消光聚酯熔体,采用巴马格的Wings-plus FDY生产设备的一步拉伸工艺生产全消光FDY纤维。该方法成本投入小,得到的全消光纤维物理指标可以满足中高端客户需求。 展开更多
关键词 全消光FDY wings-plus设备 生产技术改造
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Damage assessment of aircraft wing subjected to blast wave with finite element method and artificial neural network tool
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作者 Meng-tao Zhang Yang Pei +1 位作者 Xin Yao Yu-xue Ge 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第7期203-219,共17页
Damage assessment of the wing under blast wave is essential to the vulnerability reduction design of aircraft. This paper introduces a critical relative distance prediction method of aircraft wing damage based on the ... Damage assessment of the wing under blast wave is essential to the vulnerability reduction design of aircraft. This paper introduces a critical relative distance prediction method of aircraft wing damage based on the back-propagation artificial neural network(BP-ANN), which is trained by finite element simulation results. Moreover, the finite element method(FEM) for wing blast damage simulation has been validated by ground explosion tests and further used for damage mode determination and damage characteristics analysis. The analysis results indicate that the wing is more likely to be damaged when the root is struck from vertical directions than others for a small charge. With the increase of TNT equivalent charge, the main damage mode of the wing gradually changes from the local skin tearing to overall structural deformation and the overpressure threshold of wing damage decreases rapidly. Compared to the FEM-based damage assessment, the BP-ANN-based method can predict the wing damage under a random blast wave with an average relative error of 4.78%. The proposed method and conclusions can be used as a reference for damage assessment under blast wave and low-vulnerability design of aircraft structures. 展开更多
关键词 VULNERABILITY wing structural damage Blast wave Battle damage assessment Back-propagation artificial neural network
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In-flight deformation measurement for high-aspect-ratio wing based on 3D speckle correlation
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作者 张兴国 HU Binghua +3 位作者 WANG Yuanliang YAN Hui MA Xiaodong GE Quanbo 《High Technology Letters》 EI CAS 2023年第3期257-268,共12页
In order to get an effective solution of the in-flight wing deformation measurement for high-wing aircrafts with high-aspect-ratio,a method based on three-dimensional(3D)speckle correlation technique is proposed.First... In order to get an effective solution of the in-flight wing deformation measurement for high-wing aircrafts with high-aspect-ratio,a method based on three-dimensional(3D)speckle correlation technique is proposed.Firstly,an in-flight wing deformation measurement system with two sets of conjugate cameras is designed based on structural characteristics and test requirements of high-wing aircrafts with large-aspect-ratio.Secondly,the in-flight wing deformation measurement method based on 3D speckle correlation technique is introduced including three aspects:measuring system and wing datum calibration,speckle image matching and 3D reconstruction,and wing deformation analysis.Fi-nally,ground simulation test of dynamic deformation measurement of a scaled model wing and flight test of dynamic deformation measurement of a large transport wing are carried out.The test results show that the measuring accuracy of single point coordinate in ground simulation test is better than 0.1 mm/m,in the airborne vibration environment,the static single-point positioning accuracy is bet-ter than 5 mm,and the in-flight wing deformation measurement data is well received by the flight test engineers.This method can satisfy the requirements of stability,reliability,high precision,non-con-tact and full-field measurement for dynamic deformation measurement of aircraft wing with high-as-pect-ratio. 展开更多
关键词 HIGH-ASPECT-RATIO three-dimensional(3D)speckle wing datum
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Decomposition of Mathematical Programming Models for Aircraft Wing Design Facilitating the Use of Dynamic Programming Approach
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作者 Prashant K. Tarun Herbert W. Corley 《American Journal of Operations Research》 2023年第5期111-131,共21页
Aircraft designers strive to achieve optimal weight-reliability tradeoffs while designing an aircraft. Since aircraft wing skins account for more than fifty percent of their structural weight, aircraft wings must be d... Aircraft designers strive to achieve optimal weight-reliability tradeoffs while designing an aircraft. Since aircraft wing skins account for more than fifty percent of their structural weight, aircraft wings must be designed with utmost care and attention in terms of material types and thickness configurations. In particular, the selection of thickness at each location of the aircraft wing skin is the most consequential task for aircraft designers. To accomplish this, we present discrete mathematical programming models to obtain optimal thicknesses either to minimize weight or to maximize reliability. We present theoretical results for the decomposition of these discrete mathematical programming models to reduce computer memory requirements and facilitate the use of dynamic programming for design purposes. In particular, a decomposed version of the weight minimization problem is solved for an aircraft wing with thirty locations (or panels) and fourteen thickness choices for each location to yield an optimal minimum weight design. 展开更多
关键词 Aircraft wing Design Maximum Reliability Design Minimum Weight Design Dynamic Programming OPTIMIZATION DECOMPOSITION
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