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Chinese Journal of Aeronautics 2014年第5期27卷 1312-1317页

作者： bai jiangbo Xiong Junjiang School of Transportation Science and Engineering Beihang University

This paper seeks to outline the temperature effect on the buckling properties of ultra-thin-walled lenticular collapsible composite tube（LCCT） subjected to axial *** buckling tests of the LCCT specimens subjected to axial compression were carried out on INSTRON-500 N servo-hydraulic machine in dry state and at the temperatures of 25 C, 100 C and 80 C. The load–displacement curves and buckling initiation loads were measured and the buckling initiation mechanism was discussed from experimental observations. Experiments show that the buckling initiation load, on average, is only about 2.2% greater at the low temperature of 80 C than at the room temperature of 25 C due to the material hardening, demonstrating an insignificant increase in the buckling initiation load, whereas it is about 19.5% lower at the high temperature of 100 C than at the room temperature owing to the material softening, implying a significant decrease in the buckling initiation load. The failure mode of the LCCT in axial compression tests at three different temperatures can be reckoned to be characteristic of the buckling initiation and propagation around the central region until rupture. The finite element（FE） model is presented to simulate the buckling initiation mechanism based on the eigenvalue-based methodology. Good correlation between experimental and numerical results is achieved.

关键词： Axial compression Buckling Composite Finite element analysis Lenticular collapsible tube

Analytical model for predicting folding stable state of bistable deployable composite boom

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Chinese Journal of Aeronautics 2024年第8期37卷 460-469页

作者： Tianwei LIU jiangbo bai Nicholas FANTUZZI School of Transportation Science and Engineering Beihang UniversityBeijing 100191China Jingdezhen Research Institute of Beihang University Jingdezhen 333000China DICAM Department University of BolognaBologna 40136Italy

Bistable Deployable Composite Boom(Bi-DCB)can achieve bistable function by storing and releasing strain energy,which has a good application prospect in space *** example,it serves as the main support section of deployable structures(e.g.,solar arrays and antennas).This paper investigates folding stable state of Bi-DCB through the analytical *** on Archimedes’helix and energy principle,an analytical model for predicting folding stable state of Bi-DCB was *** failure index of Bi-DCB in folding stable state were analyzed using the Tsai-Hill criterion and the maximum stress ***,a 2400 mm long Bi-DCB was fabricated using autoclave *** prediction results of the proposed model were compared with experiments and results of two other analytical *** is shown that the proposed model shows good prediction ***,the effect of geometric parameters on folding stable state of Bi-DCB was further investigated with the aid of the proposed model.

关键词： Bistable Deployable composite boom Solar arrays Antennas Archimedes’helix Folding Failure analysis

Tear Resistance of Orthogonal Kevlar-PWF-reinforced TPU Film

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Chinese Journal of Aeronautics 2011年第1期24卷 113-118页

作者： bai jiangbo XIONG Junjiang CHENG Xu School of Transportation Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

This work seeks to investigate the notch sensitivity and fracture behaviour of orthogonal Kevlar-plain woven fabric （PWF）-reinforced thermoplastic polyurethanes （TPU） film applied to high altitude balloon. Four types of specimens are implemented to measure notched strength and fracture toughness by conducting static tension and tear tests on an MTS system respectively. The damage and failure mechanisms are discussed and the results for notched strength and tear resistance are evaluated and compared with each other. From the experiments, it is found that the notch sensitivity of the film increases with the increase in the size of the hole, but the notch sensitivity and the stress concentration of the notch are insignificant and there is a decrease of only about 4%-10% in tensile strength for the notched specimens with different hole sizes in diameter compared with the unnotched specimen. In contrast, the tear resistance containing a central slit with only 1 mm length is about half of tensile strength of the unnotched film, which implies that the tear resistance exists an significant notch sensitivity. The results of this study provide an insight into notch sensitivity and fracture behaviour of the Kevlar-PWF-reinforced TPU film and constitute a fundamental basis for the design of high altitude balloon.

关键词： fracture toughness notched strength thermoplastic polyurethanes film Kevlar fabric tear resistance

Analytical Solution for Predicting In-plane Elastic Shear Properties of 2D Orthogonal PWF Composites

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Chinese Journal of Aeronautics 2012年第4期25卷 575-583页

作者： CHENG Xu XIONG Junjiang bai jiangbo School of Transportation Science and Engineering Beihang UniversityBeijing 100191China

This paper proposes a new analytical solution to predict the shear modulus of a two-dimensional（2D） plain weave fabric（PWF） composite accounting for the interaction of orthogonal interlacing strands with coupled shear deformation modes including not only relative bending but also torsion,*** two orthogonal yarns in a micromechanical unit cell are idealized as curved beams with a path depicted by using sinusoidal shape *** internal forces and macroscopic deformations carried by the yarn families,together with macroscopic shear modulus of PWFs are derived by means of a strain energy approach founded on *** sets of experimental data pertinent to three kinds of 2D orthogonal PWF composites have been implemented to validate the new *** calculations from the new model are also compared with those by using two models in the earlier *** is shown that the experimental results correlate well with predictions from the new model.

关键词： textile composites mechanical properties shear modulus properties plain weave fabric

Analytical Solutions for Predicting Tensile and Shear Moduli of Triaxial Weave Fabric Composites

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Acta Mechanica Solida Sinica 2016年第1期29卷 59-77页

作者： jiangbo bai Junjiang Xiong Meng Liu Ziyu Man School of Transportation Science and Engineering Beihang University Beijing 100083 China

Novel micromechanical curved beam models were presented for predicting the ten- sile and shear moduli of triaxial weave fabric （TWF） composites by considering the interactions between the triaxial yarns of 0° and ±60° The triaxial yarns in micromechanieal representative unit cell （RUC） were idealized as curved beams with a path depicted using the sinusoidal shape functions, and the tensile and shear moduli of TWF composites were derived by means of the strain energy approach founded on micromechanics. In order to validate the new models, the predictions were compared with the experimental data from literature. It was shown that the predictions from the new model agree well with the experimental results. Using these models, the tensile and shear properties of TWF composites could be predicted based only on the properties of basic woven fabric.

关键词： triaxial weave fabric (TWF) composite elastic properties tension modulus shearmodulus

Electric stimulation and decimeter wave therapy improve the recovery of injured sciatic nerves

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Neural Regeneration Research 2013年第21期8卷 1974-1984页

作者： Feng Zhao Wei He Yingze Zhang Dehu Tian Hongfang Zhao Kunlun Yu jiangbo bai Department of Orthopedics the First Hospital of Hebei Medical University Department of Hand Surgery the Third Hospital of Hebei Medical University

Drug treatment, electric stimulation and decimeter wave therapy have been shown to promote the repair and regeneration of the peripheral nerves at the injured site. This study prepared a Mackinnon’s model of rat sciatic nerve compression. Electric stimulation was given immediately after neurolysis, and decimeter wave radiation was performed at 1 and 12 weeks post-operation. Histological observation revealed that intraoperative electric stimulation and decimeter wave therapy could improve the local blood circulation of repaired sites, alleviate hypoxia of compressed nerves, and lessen adhesion of compressed nerves, thereby decreasing the formation of new entrapments and enhancing compressed nerve regeneration through an improved microenvironment for regeneration. Immunohistochemical staining results revealed that intraoperative electric stimulation and decimeter wave could promote the expression of S-100 protein. Motor nerve conduction velocity and amplitude, the number and diameter of myelinated nerve fibers, and sciatic functional index were significantly increased in the treated rats. These results verified that intraoperative electric stimulation and decimeter wave therapy contributed to the regeneration and the recovery of the functions in the compressed nerves.

关键词： neural regeneration peripheral nerve injury physical therapy electric stimulation sciatic nerve compression Schwann cells functional recovery neuroregeneration

RTM成型复合材料T型接头工艺参数优化与力学性能实验研究

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复合材料学报 2009年第3期26卷 13-17页

作者：白江波熊峻江程序彭勃北京航空航天大学飞行器运用系北京100191

对树脂传递模塑(RTM)成型的复合材料T型接头进行了工艺参数优化、制备及力学性能实验研究。应用流动模拟软件,对RTM成型的复合材料T型接头进行了基体流动数值模拟,确定模具最佳注射方式和出胶口位置,并优化了影响树脂充模时间的工艺参数... 详细信息

对树脂传递模塑(RTM)成型的复合材料T型接头进行了工艺参数优化、制备及力学性能实验研究。应用流动模拟软件,对RTM成型的复合材料T型接头进行了基体流动数值模拟,确定模具最佳注射方式和出胶口位置,并优化了影响树脂充模时间的工艺参数,显著提高了RTM接头的工艺性能。根据优化工艺参数结果,制备了RTM成型的复合材料T型接头试样,并进行了拉伸和压缩试验,分析了其破坏机制。根据拉伸和压缩试验现象和结果,发现RTM成型的复合材料T型接头拉伸破坏模式主要为富树脂三角区的树脂与纤维布界面分层,其拉伸破坏主要取决于树脂基体抗剥离分层的拉伸强度;压缩破坏模式为底板中央部位的弯曲分层与折断,其压缩破坏由接头底板中的纤维布抗拉强度决定;T型接头的压缩破坏强度高于拉伸破坏强度。

关键词：复合材料树脂传递模塑(RTM) 流动模拟力学性能 T接头

基于改进CycleGAN的合成孔径雷达图像仿真

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中国科学技术大学学报 2020年第8期50卷 1181-1186页

作者：白江波杨阳张文生中国科学院自动化研究所北京100080

目标和场景的跨模态数据对于以深度神经网络为基础的跨模态检测与多模态融合算法的性能提升有着极其重大的意义.由于SAR图像的特殊性,获得成对的数据集成本很高,且现有的SAR图像生成算法大多集中在提升图像多样性与小范围场景生成,对于... 详细信息

目标和场景的跨模态数据对于以深度神经网络为基础的跨模态检测与多模态融合算法的性能提升有着极其重大的意义.由于SAR图像的特殊性,获得成对的数据集成本很高,且现有的SAR图像生成算法大多集中在提升图像多样性与小范围场景生成,对于特定场景的图像配对转化鲜有涉及.本文利用改进的循环一致性对抗网络CycleGAN实现SAR图像目标和场景的SAR图像的仿真,并利用最小二乘损失对网络进行改进,使网络性能获得提升,提高了成像的质量,论文所提方法对SAR图像进行了仿真实验,结果表明,本文方法生成图像的精细度与稳定度最优,实现了更好的仿真结果.

关键词：循环一致性对抗网络 SAR图像仿真深度残差网络最小二乘生成对抗网络

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复合材料机翼整体成型技术研究

复合材料学报 2011年第3期28卷 185-191页

作者：白江波熊峻江李雪芹罗楚养张子龙北京航空航天大学交通科学与工程学院北京100191 北京航空材料研究院先进复合材料国家重点实验室北京100095

对给定外型与尺寸的整体成型复合材料机翼进行了设计、制备及力学性能实验研究。采用有限元分析软件,对空心复合材料机翼进行静力学分析,得到了承载效率与机翼几何尺寸的关系,并确定了最优结构尺寸与复合材料纤维铺层厚度。采用石蜡芯... 详细信息

对给定外型与尺寸的整体成型复合材料机翼进行了设计、制备及力学性能实验研究。采用有限元分析软件,对空心复合材料机翼进行静力学分析,得到了承载效率与机翼几何尺寸的关系,并确定了最优结构尺寸与复合材料纤维铺层厚度。采用石蜡芯模辅助气囊法成型技术,制备了整体成型复合材料机翼,并进行了三点弯曲实验测定,分析了其破坏机制。三点弯曲实验研究发现,整体成型复合材料机翼的破坏模式为上蒙皮的局部屈曲失效,屈曲后仍有一定的承载能力。

关键词：复合材料机翼有限元石蜡芯模气囊法成型三点弯曲局部屈曲

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新中国成立以来我国边疆治理政策概述

兵团党校学报 2019年第4期 16-21页

作者：白江波西藏大学

边疆治理是中国共产党带领全国各族人民建设社会主义现代化强国的一项重要内容和方式。本文通过对新中国成立以来我国边疆治理政策的整理和分析,发现边疆治理的政策根据国家在每个阶段的发展目标呈现出不同的特质,如新中国成立初期的人... 详细信息

边疆治理是中国共产党带领全国各族人民建设社会主义现代化强国的一项重要内容和方式。本文通过对新中国成立以来我国边疆治理政策的整理和分析,发现边疆治理的政策根据国家在每个阶段的发展目标呈现出不同的特质,如新中国成立初期的人民政权巩固和民族团结、改革开放以来的以“经济发展”为中心、新时代的继承和创新发展等边疆治理政策。这些特殊的边疆治理政策是中国共产党结合每个特定的历史背景下的实际情况而创造性地提出的,为把我国建设成为社会主义现代化强国,在边疆治理方面提供了宝贵的历史经验和启示。

关键词：边疆治理政策概述