家燕翅展翼型的气动特性

对家燕滑翔时的后掠形姿态翅翼和完全展开形姿态翅翼进行了三维重构,获取了每种形态下4条不同展弦比的翼型。利用FULENT里的S-A模型对获取的翼型进行了气动特性模拟分析。结果表明:两种姿态下的翅翼最大升阻比攻角范围均在3°～5°,展弦比在35%处的翼型具有最优的气动特性。分析指出:后掠形姿态翅翼展弦比在35%处的翼型前缘半径较小,最大厚度位置靠近后缘且翼型线性曲率变化较慢,是产生较优气动特性的原因。     

弹道中段带翼弹头章动微多普勒特性研究

文中建立了带翼锥体弹头章动数学模型,分析了章动参数对目标姿态角的影响,推导了带翼弹头固定型和滑动型点散射中心的章动微多普勒理论公式,并对其进行了时频分析。基于电磁计算软件获取的目标静态电磁散射数据,结合目标运动模型合成了带翼弹头的雷达动态回波,进而获得其章动微多普勒的电磁仿真结果,验证了章动微多普勒理论公式的正确性,并给出了重要结论。     

浅析闽南民居的屋顶

介绍了闽南民居的屋顶与其他民居相比具有独特的形式——深檐长翘,就其民居屋顶形式的特征、影响因素和由此产生的艺术效果做了分析,进而阐明民居建筑的多样性和丰富性,突出闽南民居的地域特征。     

基于微系统阵列的变形翼的控制研究

针对基于微系统阵列的变形翼控制问题,搭建了一种简易分布式的、电机致动的变形翼模型。针对此模型,提出了协同控制的算法,使翼型快速变形,且在变形过程中保持翼面平滑。用李雅普诺夫定理证明了协同控制算法的收敛性。利用了Matlab／Truetime工具箱,进行了无网络、网络无丢包以及有丢包情况下的系统仿真。仿真结果表明：协同控制算法能很成功地对基于微系统阵列的变形翼进行控制。     

基于仿生平衡棒结构的共振隧穿导航传感器研究

家蝇等飞行昆虫利用后翅棒状平衡器检测哥氏力,实现了在空中飞行过程中的快速航行控制。本文基于家蝇后翅微球杆结构建立了一种仿生机械平衡器的运动学模型,并采用MATLAB分析了该模型的航行控制原理。结合家蝇的微球杆平衡结构原理和共振隧穿薄膜微结构(resonant tunneling membrane structure,RTS)的力电耦合效应,设计了一种新型的高精度仿生微型棒状导航传感器(bionic micro-stick-shaped navigation sensor,BMSSNS),并研究了BMSSNS的加工工艺、信号检测方式与路径解算方法。基于ANSYS对该BMSSNS结构进行仿真分析,仿真结果表明,给定初始边界条件下,通过测量平衡棒的哥氏力信息和驱动力信息,可积分解算出运动路径。进一步的路径实验研究结果表明,该BMSSNS能有效检测传感器的俯仰,翻滚和偏航的姿态和路径信息,其短时水平和垂直路径定位精度分别达1. 5 mm和0. 5 mm。该传感器能够在小空间、高定位精度要求的场所中实现精确路径定位。     

带翼瓦形锻件锻造工艺研究

通过分析带翼瓦形锻件特征,结合机械加工、热处理要求,制定合理的锻造成形方案,降低锻件制造成本并生产出合格锻件产品。     

Fly wing vein patterns have spatial reproducibility of a single cell

Developmental processes in multicellular organisms occur in fluctuating environments and are prone to noise, yet they produce complex patterns with astonishing reproducibility. We measure the left–right and inter-individual precision of bilaterally symmetric fly wings across the natural range of genetic and environmental conditions and find that wing vein patterns are specified with identical spatial precision and are reproducible to within a single-cell width. The early fly embryo operates at a similar degree of reproducibility, suggesting that the overall spatial precision of morphogenesis in Drosophila performs at the single-cell level. Could development be operating at the physical limit of what a biological system can achieve?     

Subtractive Structural Modification of Morpho Butterfly Wings

Different from studies of butterfly wings through additive modification, this work for the first time studies the property change of butterfly wings through subtractive modification using oxygen plasma etching. The controlled modification of butterfly wings through such subtractive process results in gradual change of the optical properties, and helps the further understanding of structural optimization through natural evolution. The brilliant color of Morpho butterfly wings is originated from the hierarchical nanostructure on the wing scales. Such nanoarchitecture has attracted a lot of research effort, including the study of its optical properties, its potential use in sensing and infrared imaging, and also the use of such structure as template for the fabrication of high‐performance photocatalytic materials. The controlled subtractive processes provide a new path to modify such nanoarchitecture and its optical property. Distinct from previous studies on the optical property of the Morpho wing structure, this study provides additional experimental evidence for the origination of the optical property of the natural butterfly wing scales. The study also offers a facile approach to generate new 3D nanostructures using butterfly wings as the templates and may lead to simpler structure models for large‐scale man‐made structures than those offered by original butterfly wings.     

On the quasi-steady aerodynamics of normal hovering flight part II: model implementation and evaluation

This paper introduces a generic, transparent and compact model for the evaluation of the aerodynamic performance of insect-like flapping wings in hovering flight. The model is generic in that it can be applied to wings of arbitrary morphology and kinematics without the use of experimental data, is transparent in that the aerodynamic components of the model are linked directly to morphology and kinematics via physical relationships and is compact in the sense that it can be efficiently evaluated for use within a design optimization environment. An important aspect of the model is the method by which translational force coefficients for the aerodynamic model are obtained from first principles; however important insights are also provided for the morphological and kinematic treatments that improve the clarity and efficiency of the overall model. A thorough analysis of the leading-edge suction analogy model is provided and comparison of the aerodynamic model with results from application of the leading-edge suction analogy shows good agreement. The full model is evaluated against experimental data for revolving wings and good agreement is obtained for lift and drag up to 90° incidence. Comparison of the model output with data from computational fluid dynamics studies on a range of different insect species also shows good agreement with predicted weight support ratio and specific power. The validated model is used to evaluate the relative impact of different contributors to the induced power factor for the hoverfly and fruitfly. It is shown that the assumption of an ideal induced power factor (k = 1) for a normal hovering hoverfly leads to a 23% overestimation of the generated force owing to flapping.     

炸鸡翅营养组分变化及关键香气成分分析

将鸡翅裹面并采用棕榈油炸,分析炸制前后鸡翅中脂肪酸和氨基酸组成变化及炸鸡翅的关键香气成分。研究发现,油炸后鸡翅肉中脂肪酸和氨基酸总含量均升高,尤其必需氨基酸与总氨基酸的比值及必需氨基酸与非必需氨基酸的比值达到了43.23%和76.16%,营养指标提高。以二氯甲烷为溶剂,采用溶剂辅助蒸发提取炸鸡翅样品中的挥发性风味物质,结合气相色谱-质谱分析鉴定出80种挥发性化合物,频率法气相色谱-嗅闻分析鉴定出51种风味物质是油炸鸡翅的气味活性化合物,GC-O检测的强势气味化合物(NIF≥55%)为2,5-二甲基-吡嗪、己醛、3-甲硫基丙醛、3-乙基-2,5-二甲基-吡嗪、2-甲基丁醛、(E)-2-壬烯醛、γ-丁内酯等36种,对这些化合物计算OAV值,确定炸鸡翅关键香气化合物(OAV≥1)25种,分别为2-甲基-3-呋喃硫醇、双(2-甲基-3-呋喃基)二硫、(E,E)-2,4-癸二烯醛、2-乙基-3,5-二甲基-吡嗪、1-辛烯-3-酮、(E)-2-癸烯醛、(E,E)-2,4-壬二烯醛、2-甲基丁醛、(E)-2-壬烯醛、3-乙基-2,5-二甲基-吡嗪、3-甲硫基丙醛、糠醛、己醛、辛醛、二甲基二硫醚、壬醛...