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侧边曲线方程 1

吉赫兹横电磁波传输室(GTEM Cell) 1

圈梁 1

大开间少墙单面走廊砌体结构 1

延性 1

性能化防火设计 1

情感分类；跨领域；关联规则 1

斧形过渡块 1

无监督领域自适应；优化步骤；跨域判别表示；语义判别 1

构造柱 1

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疏散 1

窗间墙 1

跨模态检索；鲁棒学习；对齐修正；贝塔混合模型 1

阻抗匹配 1

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Laser vision sensing based on adaptive welding for aluminum alloy

CHEN Zhixiang, SONG Yonglun, ZHANG Jun, ZHANG Wanchun, JIANG Li, XIA Xuxin

《机械工程前沿（英文）》 2007年第2卷第2期页码 218-223 doi: 10.1007/s11465-007-0038-2

摘要： A laser vision sensing based on the adaptive tungsten inert gas (TIG) welding system for large-scale aluminum alloy components was established to fit various weld groove conditions. A new type of laser vision sensor was used to precisely measure the weld groove. The joint geometry data, such as the bevel angle, the gap, the area, and the mismatch, etc., aided in assembling large-scale aerospace components before welding. They were also applied for automatic seam tracking, such as automatic torch transverse alignment and torch height adjustment in welding. An adaptive welding process was realized by automatically adjusting the wire feeding speed and the welding current according to the groove conditions. The process results in a good weld formation and high welding quality, which meet the requirements of related standards.

关键词： adjustment adaptive tungsten transverse alignment large-scale aluminum geometry

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A nano-scale alignment method for imprint lithography

WANG Li, LU Bing-heng, DING Yu-cheng, QIU Zhi-hui, LIU Hong-zhong

《机械工程前沿（英文）》 2006年第1卷第2期页码 157-161 doi: 10.1007/s11465-006-0014-2

摘要： A novel nano-scale alignment technique based on moiré signal for room-temperature imprint lithography in the submicron realm is proposed. The moiré signals generated by two pairs of quadruple gratings on mold and wafer are optically projected onto two photo-detector arrays, then the detected moiré signals are used to estimate the alignment errors in the x and y directions. The experiment results indicate that complex differential moiré signal is sensitive to relative displacement of the mold and wafer, and the alignment accuracy obtained in the x and γ directions and in θ are 20 nm , 25 nm and 1 μrad (3σ), respectively. They can meet the requirements of alignment accuracy for submicron imprint lithography.

关键词： submicron alignment accuracy nano-scale alignment quadruple room-temperature

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Detection for transverse corner cracks of steel plates’ surface using wavelet

Qiong ZHOU, Qi AN

《机械工程前沿（英文）》 2009年第4卷第2期页码 224-227 doi: 10.1007/s11465-009-0017-x

摘要： An algorithm is presented for detecting transverse corner cracks at a steel plate surface using wavelet transform. According to characteristics of transverse corner crack images, the wavelet transform is used for the multi-scale analysis of detecting the image edges and disintegrating the image into four directions at the same time. The proper threshold value is chosen to segment the image into vertical components to obtain the final detection result. The experiment shows that transverse corner cracks of steel plates can be more effectively extracted by the proposed method than the other two common methods.

关键词： transverse corner cracks defect detection multi-scales wavelet analysis

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Coordinated shift control of nonsynchronizer transmission for electric vehicles based on dynamic tooth alignment

《机械工程前沿（英文）》 2021年第16卷第4期页码 887-900 doi: 10.1007/s11465-021-0653-3

摘要： Multispeed transmissions can enhance the dynamics and economic performance of electric vehicles (EVs), but the coordinated control of the drive motor and gear shift mechanism during gear shifting is still a difficult challenge because gear shifting may cause discomfort to the occupants. To improve the swiftness of gear shifting, this paper proposes a coordinated shift control method based on the dynamic tooth alignment (DTA) algorithm for nonsynchronizer automated mechanical transmissions (NSAMTs) of EVs. After the speed difference between the sleeve (SL) and target dog gear is reduced to a certain value by speed synchronization, angle synchronization is adopted to synchronize the SL quickly to the target tooth slot’s angular position predicted by the DTA. A two-speed planetary NSAMT is taken as an example to carry out comparative simulations and bench experiments. Results show that gear shifting duration and maximum jerk are reduced under the shift control with the proposed method, which proves the effectiveness of the proposed coordinated shift control method with DTA.

关键词： electric vehicle nonsynchronizer automated mechanical transmission (NSAMT) planetary gear coordinated shift control dynamic tooth alignment

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Effect of axial load and transverse reinforcements on the seismic performance of reinforced concrete

Mounir Ait BELKACEM, Hakim BECHTOULA, Nouredine BOURAHLA, Adel Ait BELKACEM

《结构与土木工程前沿（英文）》 2019年第13卷第4期页码 831-851 doi: 10.1007/s11709-018-0513-3

摘要： The aim of this research is to assess the seismic performance of reinforced concrete columns under different axial load and transverse reinforcement ratios. These two parameters are very important as for the ductility, strength, stiffness, and energy dissipation capacity for a given reinforced concrete column. Effects of variable axial load ratio and transverse reinforcement ratio on the seismic performance of reinforced concrete columns are thoroughly analyzed. The finite element computer program Seismo-Structure was used to perform the analysis of series of reinforced concrete columns tested by the second author and other researchers. In order to reflect the reality and grasp the actual behavior of the specimens, special attention was paid to select the models for concrete, confined concrete, and steel components. Good agreements were obtained between the experimental and the analytical results either for the lateral force-drift relationships or for the damage progress prediction at different stages of the loading.

关键词： reinforced concrete columns axial load transverse reinforcement ductility

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基于对齐自修正的鲁棒跨模态检索 Research Article

郭金一1,丁洁玉2

《信息与电子工程前沿（英文）》 2023年第24卷第10期页码 1403-1415 doi: 10.1631/FITEE.2200514

摘要：跨模态检索通过为不同模态数据建立一致的对齐方式来实现模态间的相互检索。目前多种跨模态检索方法已被提出并取得良好性能。这些方法使用干净对齐的跨模态数据进行训练。虽然这些数据在语义上是匹配的，但相较于互联网上容易获得的噪声对齐的数据（即成对但在语义上不匹配），标注成本很高。当用噪声对齐的数据训练这些模型时，它们的性能会急剧下降。因此，本文提出一种对齐自修正的鲁棒跨模态检索算法（RCAR），显著降低了噪声数据对模型的影响。具体来说，RCAR首先进行多任务学习，减缓模型对噪声数据的过拟合，使数据分离。然后，利用两成分的贝塔混合模型将数据分为干净数据和噪声数据，并根据后验概率修正对齐标签。此外，在噪声对齐范式中定义两种噪声类型：部分噪声数据和完全噪声数据。实验结果表明，与当下流行的跨模态检索方法相比，RCAR在两种类型的噪声下都能取得更稳健的性能。

关键词：跨模态检索；鲁棒学习；对齐修正；贝塔混合模型

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Investigating the influence of delamination on the stiffness of composite pipes under compressive transverse

Sattar MALEKI, Roham RAFIEE, Abolfazl HASANNIA, Mohammad Reza HABIBAGAHI

《结构与土木工程前沿（英文）》 2019年第13卷第6期页码 1316-1323 doi: 10.1007/s11709-019-0555-1

摘要： The effect of delamination on the stiffness reduction of composite pipes is studied in this research. The stiffness test of filament wound composite pipes is simulated using cohesive zone method. The modeling is accomplished to study the effect of the geometrical parameters including delamination size and its position with respect to loading direction on stiffness of the composite pipes. At first, finite element results for stiffness test of a perfect pipe without delamination are validated with the experimental results according to ASTM D2412. It is seen that the finite element results agree well with experimental results. Then the finite element model is developed for composite pips with delaminated areas with different primary shapes. Thus, the effect of the size of delaminated region on longitudinal and tangential directions and also its orientation with respect to loading direction on delamination propagation and stiffness reduction of the pipes is assessed.

关键词： delamination composite pipes stiffness test cohesive zone method

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Weakening behavior of waterproof performance in joints of shield tunnels under adjacent constructions

《结构与土木工程前沿（英文）》页码 884-900 doi: 10.1007/s11709-022-0912-3

摘要： Groundwater leakage in shield tunnels poses a threat to the safety and durability of tunnel structures. Disturbance of adjacent constructions during the operation of shield tunnels frequently occurs in China, leading to deformation of tunnel lining and leakage in joints. Understanding the impact of adjacent constructions on the waterproofing performance of the lining is critical for the protection of shield tunnels. In this study, the weakening behavior of waterproof performance was investigated in the joints of shield tunnels under transverse deformation induced by adjacent construction. First, the relationship between the joint opening and transverse deformation under three typical adjacent constructions (upper loading, upper excavation, and side excavation) was investigated via elaborate numerical simulations. Subsequently, the evolution of the waterproof performance of a common gasket with a joint opening was examined by establishing a coupled Eulerian–Lagrangian model of joint seepage, and a formula describing the relationship between waterproof performance and joint opening was proposed. Finally, the weakening law of waterproofing performance was investigated based on the results of the aforementioned studies. It was determined that the joints with the greatest decline in waterproof performance were located at the tunnel shoulder in the upper loading case, tunnel crown in the upper excavation case, and tunnel shoulder in the side excavation case. When the waterproof performance of these joints decreased to 50% and 30%, the transverse deformations were 60 and 90 mm under upper loading, 90 and 140 mm under upper excavation, and 45 and 70 mm under side excavation, respectively. The results provide a straightforward reference for setting a controlled deformation standard considering the waterproof performance.

关键词： shield tunnel waterproof performance horizontal transverse deformation joint opening weakening behavior

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Bending and vibration of a discontinuous beam with a curvic coupling under different axial forces

Heng LIU, Jie HONG, Dayi ZHANG

《机械工程前沿（英文）》 2020年第15卷第3期页码 417-429 doi: 10.1007/s11465-019-0584-4

摘要： The transverse stiffness and vibration characteristics of discontinuous beams can significantly differ from those of continuous beams given that an abrupt change in stiffness may occur at the interface of the former. In this study, the equations for the deflection curve and vibration frequencies of a simply supported discontinuous beam under axial loads are derived analytically on the basis of boundary, continuity, and deformation compatibility conditions by using equivalent spring models. The equation for the deflection curve is solved using undetermined coefficient methods. The normal function of the transverse vibration equation is obtained by separating variables. The differential equations for the beam that consider moments of inertia, shearing effects, and gyroscopic moments are investigated using the transfer matrix method. The deflection and vibration frequencies of the discontinuous beam are studied under different axial loads and connection spring stiffness. Results show that deflection decreases and vibration frequencies increase exponentially with increasing connection spring stiffness. Moreover, both variables remain steady when connection spring stiffness reaches a considerable value. Lastly, an experimental study is conducted to investigate the vibration characteristics of a discontinuous beam with a curvic coupling, and the results exhibit a good match with the proposed model.

关键词： discontinuous beam bending stiffness transverse vibration axial loads gyroscopic moments

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Flexural and longitudinal shear performance of precast lightweight steel–ultra-high performance concrete composite beam

《结构与土木工程前沿（英文）》 2023年第17卷第5期页码 704-721 doi: 10.1007/s11709-023-0941-6

摘要： In this study, the flexural and longitudinal shear performances of two types of precast lightweight steel–ultra-high performance concrete (UHPC) composite beams are investigated, where a cluster UHPC slab (CUS) and a normal UHPC slab (NUS) are connected to a steel beam using headed studs through discontinuous shear pockets and full-length shear pockets, respectively. Results show that the longitudinal shear force of the CUS is greater than that of the NUS, whereas the interfacial slip of the former is smaller. Owing to its better integrity, the CUS exhibits greater flexural stiffness and a higher ultimate bearing capacity than the NUS. To further optimize the design parameters of the CUS, a parametric study is conducted to investigate their effects on the flexural and longitudinal shear performances. The square shear pocket is shown to be more applicable for the CUS, as the optimal spacing between two shear pockets is 650 mm. Moreover, a design method for transverse reinforcement is proposed; the transverse reinforcement is used to withstand the splitting force caused by studs in the shear pocket and prevent the UHPC slab from cracking. According to calculation results, the transverse reinforcement can be canceled when the compressive strength of UHPC is 150 MPa and the volume fraction of steel fiber exceeds 2.0%.

关键词： precast steel–UHPC composite beam flexural performance longitudinal shear performance parametric study transverse reinforcement ratio

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无监督域自适应的动态参数化学习 Research Article

蒋润华1,2,韩亚洪1,2

《信息与电子工程前沿（英文）》 2023年第24卷第11期页码 1616-1632 doi: 10.1631/FITEE.2200631

摘要：无监督领域自适应通过学习域不变表示实现神经网络从有标签数据组成的源域到无标签数据组成的目标域迁移。近期研究通过直接匹配这两个域的边缘分布实现这一目标。然而，已有研究大多数忽略域对齐和语义判别学习之间的动态平衡，因此容易受负迁移和异常样本影响。为解决这些问题，引入动态参数化学习框架。首先，通过探索领域级语义知识，提出动态对齐参数自适应地调整域对齐和语义判别学习的优化过程。此外，为获得判别能力强和域不变的表示，提出在源域和目标域上对齐优化过程。本文通过综合实验证明了所提出方法的有效性，并在3个视觉任务的7个数据集上进行广泛比较，证明可行性。

关键词：无监督领域自适应；优化步骤；跨域判别表示；语义判别

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Vibration analysis of a simply supported beam under moving mass based on moving finite element method

Zhuchao YE, Huaihai CHEN,

《机械工程前沿（英文）》 2009年第4卷第4期页码 397-400 doi: 10.1007/s11465-009-0044-7

摘要： In this paper, a moving finite element (MFE) method is proposed to perform the dynamic analysis of a simply supported beam for a moving mass (MM). The MFE method treats the moving mass as a moving part of the entire system, so that the transverse inertial effects caused by the moving mass may easily be taken into account. The solution to the beam’s dynamic behaviors including its displacement is obtained via a Newmark-β method; the effects of the velocity and weight of the MM on the beam’s dynamic behaviors are further discussed. The numerical examples show that the inertial effects of the MM significantly affect the transverse responses of the simply supported beam.

关键词： simply supported beam moving mass (MM) transverse vibration moving finite element (MFE)

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基于关联规则进行词对齐的跨领域情感分类算法 None

Xi-bin JIA, Ya JIN, Ning LI, Xing SU, Barry CARDIFF, Bir BHANU

《信息与电子工程前沿（英文）》 2018年第19卷第2期页码 260-272 doi: 10.1631/FITEE.1601679

摘要：文本情感分类被应用于企业用户管理系统，通过自动对诸如评论、博客等带有情感倾向性文字进行分析，帮助商家更好地了解用户对商品或者服务的态度。然而，评论和博客等内容常源于不同应用领域，为每个领域训练一个能准确预测情感倾向的分类器非常困难。主要原因是，在不同领域，人们通常会用不同特征词表达相同情感，并且难以找到一个直接的映射函数，以建立不同领域特征词间的映射关系，从而消除领域间差异。因此，将某个领域训练好的分类器直接应用到另一个领域时，会因为领域间差异使得分类器准确率急速下降。本文提出一个新的基于关联规则进行特征词对齐的跨领域情感分类算法，该算法通过在同一领域中挖掘具有强关联关系的领域共享词和领域专有词词对，建立直接映射关系，并以领域共享词为桥梁，在不同领域的特征专有词之间建立间接映射关系，从而在一定程度上消除了源领域和目标领域之间的差异，有效提升了跨领域情感分类准确率。在亚马逊数据库上的实验结果证明该算法提高了跨领域情感分类性能。

关键词：情感分类；跨领域；关联规则

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长大公路隧道火灾安全疏散性能化设计与分析

陈长坤,徐志胜

《中国工程科学》 2007年第9卷第9期页码 78-83

摘要：

基于性能化防火设计方法，分析火灾条件下长大公路隧道内人员疏散行为的特点，给出隧道内人员疏散的安全判据，并结合某隧道的结构及车流特征对人员疏散过程进行了数值模拟研究，分析隧道在正常通车和局部行车堵塞时，不同火源位置、横通道间距与横通道宽度对人员疏散时间及安全状态的影响。结果表明,与建筑内人员疏散不同，长大公路隧道内火灾的可用安全疏散时间(ASET)与需要的安全疏散时间(RSET)均为沿隧道长度方向位置的函数。隧道内人员安全疏散的时间曲线在各横通道疏散口出现峰值，这主要是受到横通道通行能力的限制，各疏散口人员集聚等待所致。当隧道发生局部堵塞时，横通道口需要的安全疏散时间显著增加，危险性也急剧增大。隧道内人员疏散的性能化防火设计应综合考虑火源位置对人员载荷及疏散口位置可用安全疏散时间的影响。该研究为公路隧道火灾安全疏散设施的优化设计提供依据。

关键词：疏散火灾隧道横通道性能化防火设计