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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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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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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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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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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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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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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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Kinematic and Aerodynamic Modelling of Bi- and Quad-Wing Flapping Wing Micro-Air-Vehicle 被引量:1
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作者 Harijono Djojodihardjo Alif Syamim S. Ramli +1 位作者 Surjatin Wiriadidjaja Azmin Shakrine Mohd Rafie 《Advances in Aerospace Science and Technology》 2016年第3期83-101,共19页
A generic approach to model the kinematics and aerodynamics of flapping wing ornithopter has been followed, to model and analyze a flapping bi- and quad-wing ornithopter and to mimic flapping wing biosystems to produc... A generic approach to model the kinematics and aerodynamics of flapping wing ornithopter has been followed, to model and analyze a flapping bi- and quad-wing ornithopter and to mimic flapping wing biosystems to produce lift and thrust for hovering and forward flight. Considerations are given to the motion of a rigid and thin bi-wing and quad-wing ornithopter in flapping and pitching motion with phase lag. Basic Unsteady Aerodynamic Approach incorporating salient features of viscous effect and leading-edge suction are utilized. Parametric study is carried out to reveal the aerodynamic characteristics of flapping bi- and quad-wing ornithopter flight characteristics and for comparative analysis with various selected simple models in the literature, in an effort to develop a flapping bi- and quad-wing ornithopter models. In spite of their simplicity, results obtained for both models are able to reveal the mechanism of lift and thrust, and compare well with other work. 展开更多
关键词 Bi-wing Ornithopter Flapping wing Aerodynamics Flapping wing Ornithopter Micro Air Vehicle Quad-wing Ornithopter
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Wings-plus设备生产全消光FDY工艺探讨
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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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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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WiNG节点仪器应用简介
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作者 吴青松 佴小君 +1 位作者 刘都让 付淼星 《物探装备》 2023年第5期299-302,306,共5页
WiNG节点仪器是Sercel公司的第三代节点仪器产品,具有轻便、续航时间长、无线实时质控、数据下载与充电一体化、数据管理软件操作简单、桩号自动拟合、RFID标签等特点;其无线质控有近距离的点对点直连,用于获取详细的节点运行状态数据... WiNG节点仪器是Sercel公司的第三代节点仪器产品,具有轻便、续航时间长、无线实时质控、数据下载与充电一体化、数据管理软件操作简单、桩号自动拟合、RFID标签等特点;其无线质控有近距离的点对点直连,用于获取详细的节点运行状态数据、运行测试、查看噪音等,和通过接力回传实现远距离节点站状态结果信息获取。2022年底国内首次引进该节点仪器系统并在中石化山东某三维地震勘探工区实施了大规模应用,取得了良好的应用效果。本文结合实际应用介绍了WiNG节点仪器的功能特点。 展开更多
关键词 地震勘探 节点仪器 wing 远程无线实时质控
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Structural Design and Analysis of Small Flapping Wing Aircraft Based on the Crank Slider Mechanism
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作者 Minghui Ma Fengli Liu Yongping Hao 《Journal of Electronic Research and Application》 2023年第1期25-31,共7页
In this project,the miniaturization of the aircraft was realized under the premise of strong maneuverability,high concealability,and driving a certain load,and the flight mode and structural characteristics of birds w... In this project,the miniaturization of the aircraft was realized under the premise of strong maneuverability,high concealability,and driving a certain load,and the flight mode and structural characteristics of birds were imitated.A small bionic flapping wing aircraft was built.The flapping of the wing was realized by the crank slider mechanism,and the sizes of each part were calculated according to the bionics formula.The wingspan was 360.37 mm,the body width was 22 mm,the body length was 300 mm,the wing area was 0.05 m^(2),the flapping amplitude was 71°.ADAMS software was used to simulate the dynamics of the designed aircraft,and the variation of flapping amplitude and angular velocity during the movement of the aircraft was obtained,which verified the feasibility of the mechanism.The prototype aircraft was made for flight test,and the designed bionic flapping wing aircraft achieved the expected effect.It provides a theoretical basis and data support for the design and manufacture of small flapping wing aircraft. 展开更多
关键词 Flapping wing aircraft Structural design Dynamic simulation
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Navigating Temporal and Spatial Dimensions:Unveiling the Fictional Essence and Authenticity in the Narrative of The Rise and Fall of Wing Shing Street
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作者 Xiaohan Lu Jing Yang 《Journal of Contemporary Educational Research》 2023年第11期6-10,共5页
The novel The Rise and Fall of Wing Shing Street delves into the reality of Hong Kong residents deeply attuned to spatial awareness but detached from temporal significance,entangling emotions surrounding time and spac... The novel The Rise and Fall of Wing Shing Street delves into the reality of Hong Kong residents deeply attuned to spatial awareness but detached from temporal significance,entangling emotions surrounding time and space.Through narrative interruption and extension,the author portrays the genuine struggles of Hong Kong inhabitants-juxtaposing the blurred boundaries of time and space and the inherent rootlessness of reality within a fictionalized framework.Emphasizing the 20th-century human condition,wherein spatial awareness overshadows temporal understanding,the novel underscores the consequences:a loss of history and cultural identity.With a fresh perspective,the narrative explores the interplay of time and space,accentuating both the fictitious and authentic dimensions.This prompts readers to reconsider their history,culture,and the current moment,ultimately highlighting the pivotal role of temporal awareness. 展开更多
关键词 The Rise and Fall of wing Shing Street Spatial awareness Temporal awareness Rootlessness Cultural identity Return of the heart
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Insights into wing dimorphism in worldwide agricultural pest and hostalternating aphid Aphis gossypii 被引量:3
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作者 JI Jichao HUANGFU Ningbo +4 位作者 LUO Junyu GAO Xueke NIU Lin ZHANG Shuai CUI Jinjie 《Journal of Cotton Research》 2021年第1期38-49,共12页
Background:The worldwide pest Aphis gossypii has three-winged morphs in its life cycle,namely,winged parthenogenetic female(WPF),winged gynopara(GP),and winged male,which are all produced by a wingless parthenogenetic... Background:The worldwide pest Aphis gossypii has three-winged morphs in its life cycle,namely,winged parthenogenetic female(WPF),winged gynopara(GP),and winged male,which are all produced by a wingless parthenogenetic female(WLPF).Most studies on A.gossypii have focused on WPF,while few have investigated GP and male.The shared molecular mechanism underlying the wing differentiation in the three wing morphs of A.gossypii remains unknown.The wing differentiation of WPF was explored in a previous study.Herein,GP and male were induced indoors.The characters of the body,internal genitals,wing veins,and fecundity of GP and male were compared with those of WPF or WLPF.Compared with WLPF,the shared and separate differentially expressed genes(DEGs)were identified in these three-wing morphs.Results:Newly-born nymphs reared in short photoperiod condition(8 L:16D,18°C)exclusively produced gynoparae(GPe)and males in adulthood successively,in which the sex ratio was GP biased.A total of 14 GPe and 9 males were produced by one mother aphid.Compared with WLPF,the three-wing morphs exhibited similar morphology and wing vein patterns but were obviously discriminated in the length of fore-and underwings,reproductive system,and fecundity.A total of 37090 annotated unigenes were obtained from libraries constructed using the four morphs via RNA sequencing(RNA-Seq).In addition,10867 and 19334 DEGs were identified in the pairwise comparison of GP versus WLPF and male versus WLPF,respectively.Compared with WLPF,the winged morphs demonstrated 2335 shared DEGs(1658 upregulated and 677 downregulated).The 1658 shared upregulated DEGs were enriched in multiple signaling pathways,including insulin,FoxO,MAPK,starch and sucrose metabolism,fatty acid biosynthesis,and degradation,suggesting their key roles in the regulation of wing plasticity in the cotton aphid.Forty-four genes that spanned the range of differential expression were chosen to validate statistical analysis based on RNA-Seq through the reverse transcription quantitative real time polymerase chain reaction(RT-qPCR).The comparison concurred with the expression pattern(either up-or downregulated)and supported the accuracy and reliability of RNA-Seq.Finally,the potential roles of DEGs related to the insulin signaling pathway in wing dimorphism were discussed in the cotton aphid.Conclusions:The present study established an efficiently standardized protocol for GP and male induction in cotton aphid by transferring newly-born nymphs to short photoperiod conditions(8 L:16D,18°C).The external morphological characters,especially wing vein patterns,were similar among WPFs,GPe,and males.However,their reproductive organs were strikingly different.Compared with WLPF,shared(2335)and exclusively(1470 in WLPF,2419 in GP,10774 male)expressed genes were identified in the three-wing morphs through RNA-Seq,and several signaling pathways that are potentially involved in their wing differentiation were obtained,including insulin signaling,starch and sucrose metabolism. 展开更多
关键词 Cotton aphid wing differentiation wing plasticity winged parthenogenetic female Gynopara Male
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模糊WINGS视角下的ANP加权矩阵新构造方法 被引量:7
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作者 孙永河 李春好 +1 位作者 谢晖 段万春 《计算机工程与应用》 CSCD 2014年第12期26-32,37,共8页
构造因素集加权矩阵是ANP系统未加权超矩阵到加权超矩阵转化的一个关键技术。然而从已有的三种构造方法看,两两比较法比较机理混乱,而等权矩阵假设构造法通常是无效的,并且基于DEMATEL(决策试行与评价实验室)的构造方法不仅存在忽视因... 构造因素集加权矩阵是ANP系统未加权超矩阵到加权超矩阵转化的一个关键技术。然而从已有的三种构造方法看,两两比较法比较机理混乱,而等权矩阵假设构造法通常是无效的,并且基于DEMATEL(决策试行与评价实验室)的构造方法不仅存在忽视因素集自身强度的内在不足,而且也难以反映专家在对因素集之间影响关系判断时存在的"不精确性"。为克服上述缺陷,提出一种模糊WINGS(加权影响情景下的非线性测度体系)视角下的ANP因素集加权矩阵新构造方法。该方法一方面给出改进后的模糊DELPHI决策程序,充分考虑了专家判断过程中的"不精确性"。另一方面,系统提出模糊WINGS的方法思路,在系统因素集影响关系判别时充分考虑了因素集的自我影响强度,使因素集直接影响矩阵的构造更为合理。实例对比验证结果表明,该方法是科学合理的,有着较强的实践应用可操作性。 展开更多
关键词 模糊加权影响情景下的非线性测度体系(wingS) 网络分析法 超矩阵 加权矩阵
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Longitudinal Aerodynamic Characteristics of the Novel Wing-Body
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作者 MOHAMED Kaka 《Computer Aided Drafting,Design and Manufacturing》 2007年第2期28-36,共9页
The Longitudinal Aerodynamic Characteristics (LACs)of a wing-body without tail unit is computed and tested in wind tunnel. The empirical formulas of Datcom and some other authors are applied to estimate the basic Ae... The Longitudinal Aerodynamic Characteristics (LACs)of a wing-body without tail unit is computed and tested in wind tunnel. The empirical formulas of Datcom and some other authors are applied to estimate the basic Aerodynamic Coefficients. Two wing options are covered as analysis space, namely, the double-delta wing and streak wing, getting two analysis groups respectively. Good agreement between the computation results and the wind tunnel tests shows that the methodology presented is a simple and reliable way to calculate this kind of novel wing-body configurations. 展开更多
关键词 longitudinal aerodynamic characteristics double-delta wing streak wing wingbody
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A computational study of the wing-wing and wing-body interactions of a model insect 被引量:17
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作者 Xin Yu Mao Sun 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第4期421-431,共11页
The aerodynamic interaction between the contralateral wings and between the body and wings of a model insect are studied, by using the method of numerically solving the Navier-Stokes equations over moving overset grid... The aerodynamic interaction between the contralateral wings and between the body and wings of a model insect are studied, by using the method of numerically solving the Navier-Stokes equations over moving overset grids, under typical hovering and forward flight conditions. Both the interaction between the contralateral wings and the interaction between the body and wings are very weak, e.g. at hovering, changes in aerodynamic forces of a wing due to the present of the other wing are less than 3% and changes in aerodynamic forces of the wings due to presence of the body are less than 2%. The reason for this is as following. During each down- or up-stroke, a wing produces a vortex ring, which induces a relatively large jet-like flow inside the ring but very small flow outside the ring. The vortex rings of the left and right wings are on the two sides of the body. Thus one wing is outside vortex ring of the other wing and the body is outside the vortex rings of the left and right wings, resulting in the weak interactions. 展开更多
关键词 INSECT AERODYNAMICS wing/winginteraction wing/body interaction
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The effects of corrugation and wing planform on the aerodynamic force production of sweeping model insect wings 被引量:13
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作者 Guoyu Luo Mao Sun 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第6期531-541,共11页
The effects of corrugation and wing planform (shape and aspect ratio) on the aerodynamic force production of model insect wings in sweeping (rotating after an initial start) motion at Reynolds number 200 and 3500 ... The effects of corrugation and wing planform (shape and aspect ratio) on the aerodynamic force production of model insect wings in sweeping (rotating after an initial start) motion at Reynolds number 200 and 3500 at angle of attack 40℃ are investigated, using the method of computational fluid dynamics. A representative wing corrugation is considered. Wing-shape and aspect ratio (AR) of ten representative insect wings are considered; they are the wings of fruit fly, cranefly, dronefly, hoverfly, ladybird, bumblebee, honeybee, lacewing (forewing), hawkmoth and dragon- fly (forewing), respectively (AR of these wings varies greatly, from 2.84 to 5.45). The following facts are shown. (1) The corrugated and flat-plate wings produce approximately the same aerodynamic forces. This is because for a sweeping wing at large angle of attack, the length scale of the corrugation is much smaller than the size of the separated flow region or the size of the leading edge vortex (LEV). (2) The variation in wing shape can have considerable effects on the aerodynamic force; but it has only minor effects on the force coefficients when the velocity at r2 (the radius of the second :moment of wing area) is used as the reference velocity; i.e. the force coefficients are almost unaffected by the variation in wing shape. (3) The effects of AR are remarkably small: whenAR increases from 2.8 to 5.5, the force coefficients vary only slightly; flowfield results show that when AR is relatively large, the part of the LEV on the outer part of the wings sheds during the sweeping motion. As AR is increased, on one hand, the force coefficients will be increased due to the reduction of 3-dimensional flow effects; on the other hand, they will be decreased due to the shedding of part of the LEV; these two effects approximately cancel each other, resulting in only minor change of the force coefficients. 展开更多
关键词 insect flight - Sweeping wing Unsteady aerodynamics wing corrugation Planform
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