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个人热管理 1

仿生材料 1

循环移位操作；自路由；控制信息生成算法；Inverse butterfly网络 1

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Bioinspired C/TiO

Jian LI, Likun GAO, Wentao GAN

《农业科学与工程前沿（英文）》 2017年第4卷第4期页码 459-464 doi: 10.15302/J-FASE-2017178

摘要： butterfly wings were replicated by a sol-gel method and a calcination process, which could take advantage of the spatial features of the wing to enhance their photocatalytic properties. Hierarchical structures of -carbon-TiO (PP-C-TiO ) were confirmed by SEM observations. By applying the Brunauer-Emmett-Teller method, it was concluded that in the presence of wings the product shows higher surface area with respect to the pure TiO made in the absence of the wings. The higher specific surface area is also beneficial for the improvement of photocatalytic property. Furthermore, the conduction and valence bands of the PP-C-TiO are more negative than the corresponding bands of pure TiO , allowing the electrons to migrate from the valence band to the conduction band upon absorbing visible light. That is, the presence of C originating from wings in the PP-C-TiO could extend the photoresponsiveness to visible light. This strategy provides a simple method to fabricate a high-performance photocatalyst, which enables the simultaneous control of the morphology and carbon element doping.

关键词： bioinspired butterfly wings C/TiO₂ photocatalyst visible light

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Parametric computational study on butterfly-shaped hysteretic dampers

Ali Reza FARZAMPOUR, Matthew Roy EATHERTON

《结构与土木工程前沿（英文）》 2019年第13卷第5期页码 1214-1226 doi: 10.1007/s11709-019-0550-6

摘要： A parametric computational study is conducted to investigate the shear yielding, flexural yielding, and lateral torsional buckling limit states for butterfly-shaped links. After validating the accuracy of the finite element (FE) modeling approach against previous experiments, 112 computational models with different geometrical properties were constructed and analyzed including consideration of initial imperfections. The resulting yielding moment, corresponding critical shear force, the accumulation of plastic strains through the length of links as well as the amount of energy dissipated are investigated. The results indicate that as the shape of the butterfly-shaped links become too straight or conversely too narrow in the middle, peak accumulated plastic strains increase. The significant effect of plate thickness on the buckling limit state is examined in this study. Results show that overstrength for these links (peak force divided by yield force) is between 1.2 and 4.5, with straight links producing larger overstrength. Additionally, proportioning the links to delay buckling, and designing the links to yield in the flexural mode are shown to improve energy dissipation.

关键词： structural fuse hysteretic damper finite element analysis energy dissipation initial imperfection butterfly-shaped links

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基于Inverse Butterlfy网络的高效可重构循环移位单元 Article

Chao MA, Zi-bin DAI, Wei LI, Hai-juan ZANG

《信息与电子工程前沿（英文）》 2017年第18卷第11期页码 1784-1794 doi: 10.1631/FITEE.1601265

摘要：本文提出了一种利用inverse butterfly网络的自路由特性完成循环移位、短字循环移位等操作的可重构控制信息生成算法。

关键词：循环移位操作；自路由；控制信息生成算法；Inverse butterfly网络

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Investigations on color variations of Morpho rhetenor butterfly wing scales

Guanglan LIAO, Haibo ZUO, Xuan JIANG, Xuefeng YANG, Tielin SHI

《机械工程前沿（英文）》 2012年第7卷第4期页码 394-400 doi: 10.1007/s11465-012-0347-y

摘要：

Experiments and simulations are carried out to investigate the optical properties of butterfly wing scales. The upper surface of a male butterfly wing presents a single-layer of scales, the microstructures of which are responsible for the brilliant blue color. The color varies from cyan blue to yellow green and soon afterwards returns back to cyan blue when some ethanol is dropped on the upper surface. At the start of the ethanol volatilization process, the reflection spectrum remains stable. As the ethanol further volatilizes, the peak reflectance decreases slightly, then increases dramatically. Meanwhile, the peak wavelength keeps approximately constant, then decreases, and keeps almost stable at the end of the process. Therefore, the optical properties depend strongly on the varying ambient conditions, including the refractive index and the thickness of the packing medium. Moreover, the possible causes for the scales in dark green region after several dropping ethanol experiments are clarified. This research benefits our understanding of the color variation mechanisms of the wing scales, and provides inspiration for further studies and applications.

关键词： Morpho rhetenor microstructures color variations ambient medium

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Vibration-based crack prediction on a beam model using hybrid butterfly optimization algorithm with artificial

Abdelwahhab KHATIR; Roberto CAPOZUCCA; Samir KHATIR; Erica MAGAGNINI

《结构与土木工程前沿（英文）》 2022年第16卷第8期页码 976-989 doi: 10.1007/s11709-022-0840-2

摘要： Vibration-based damage detection methods have become widely used because of their advantages over traditional methods. This paper presents a new approach to identify the crack depth in steel beam structures based on vibration analysis using the Finite Element Method (FEM) and Artificial Neural Network (ANN) combined with Butterfly Optimization Algorithm (BOA). ANN is quite successful in such identification issues, but it has some limitations, such as reduction of error after system training is complete, which means the output does not provide optimal results. This paper improves ANN training after introducing BOA as a hybrid model (BOA-ANN). Natural frequencies are used as input parameters and crack depth as output. The data are collected from improved FEM using simulation tools (ABAQUS) based on different crack depths and locations as the first stage. Next, data are collected from experimental analysis of cracked beams based on different crack depths and locations to test the reliability of the presented technique. The proposed approach, compared to other methods, can predict crack depth with improved accuracy.

关键词： damage prediction ANN BOA FEM experimental modal analysis

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Stress induced polarization switching and coupled hysteretic dynamics in ferroelectric materials

Linxiang WANG, Roderick MELNIK, Fuzai LV

《机械工程前沿（英文）》 2011年第6卷第3期页码 287-291 doi: 10.1007/s11465-011-0230-2

摘要：

The dynamic responses of ferroelectric materials upon external mechanical and electrical stimulations are inherently nonlinear and coupled. In the current paper, a macroscopic differential model is constructed for the coupled hysteretic dynamics via modeling the orientation switching induced in the materials. A non-convex potential energy is constructed with both mechanic and electric field contributions. The governing equations are formulated as nonlinear ordinary differential equations by employing the Euler-Lagrange equation, and can be easily recast into a state space form. Hysteresis loops associated with stress induced polarization switching and butterfly-shaped behavior in ferroelectric materials are also successfully captured. The effects of mechanical loadings on the electrically induced switching are numerically investigated, as well as the mechanically-induced switching with various bias electric fields.

关键词： differential model state space electromechanical switching butterfly effects hysteresis

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基于蝶翅三级微纳米结构的定制光子工程辐射制冷纺织品 Article

郭竑宇, 牛田野, 俞建勇, 王学利, 斯阳

《工程（英文）》 2023年第31卷第12期页码 120-126 doi: 10.1016/j.eng.2023.07.019

摘要：

通过将被动辐射制冷策略与个人热管理技术相结合，为缓解人体在户外活动中的热不适感提供了新的思路。然而，目前大多数被动辐射制冷材料在穿着舒适性和耐用性方面存在不足。本文采用微阵列技术，成功制备出了具有辐射制冷能力的定制光子工程可穿戴纺织品。所开发的辐射制冷纺织品（RCTs）具有一定的透气透湿性、结构稳定性和扩展光谱响应性（太阳光反射率91.7%、大气窗口发射率95.8%）。在正午炎热环境的室外降温测试中，RCTs所覆盖的皮肤模拟器温度比棉织物低4.4 ℃。这种仿生结构的开发为可穿戴、热湿舒适和结构稳定的辐射制冷纺织品在个人热管理领域的应用提供了新的见解。

关键词：仿生材料个人热管理纺织品辐射制冷