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动力特性 6

动态规划 5

动力响应 3

力学性能 2

动力学 2

动力气垫 2

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动态模拟 2

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海上风电场 2

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6G；广域覆盖信令小区；多维资源分配；深度Q网络（DQN） 1

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

《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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Numerically investigating the crushing of sandstone by a tooth hob

《结构与土木工程前沿（英文）》页码 964-979 doi: 10.1007/s11709-023-0978-6

摘要： To investigate the mechanical process that occurs between rocks and tooth hobs, the crushing of sandstone with a tooth hob was simulated using reconstructed multi-mineral mesoscopic numerical models of various grain-sized sandstone samples. When a piece of sandstone is crushed by the tooth of a hob rolling at a constant speed, the resultant reaction forces of the sandstone on the tooth first hinder and then contribute to the rolling of the hob. The absolute value of the longitudinal reaction force is significantly higher than that of the lateral reaction force. Because the tooth was subjected to reaction forces from the sandstone, forces and moments were applied to the hob in order to keep the hob rolling. The applied forces were equal in value and opposite in direction to the reaction forces of the sandstone on the tooth. Three typical curves of the work done by the applied forces and moment were obtained, and the contribution of the applied lateral force and moment to the total work done for crushing sandstones was variable; however, no work was done by the applied longitudinal force. Moreover, the applied longitudinal force and total work were positively correlated with the strength of sandstone samples. The total work, applied forces, and moment increased with the maximum penetration depth of the tooth in the sandstone.

关键词： sandstone tooth hob crushing process reaction force numerical simulation

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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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Experimental investigation of fatigue behavior of spur gear in altered tooth-sum gearing

H. K. SACHIDANANDA, Joseph GONSALVIS, H. R. PRAKASH

《机械工程前沿（英文）》 2012年第7卷第3期页码 268-278 doi: 10.1007/s11465-012-0331-6

摘要：

This paper deals with the contact stress, power loss, and pitting of spur gear tooth in altered tooth-sum gearing for a tooth-sum of 100 teeth when altered by±4% tooth-sum. Analytical and experimental methods were performed to investigate and compare the altered tooth-sum gearing against the standard tooth-sum gearing. The experiments were performed using a power recirculating type test rig. The tooth loads for the experimental investigations were determined considering the surface durability of gears. A clear picture of the surface damage was obtained using a scanning electron microphotograph. The negative alteration in the tooth-sum performed better than the positive alteration in a tooth-sum operating between specified center distances.

关键词： spur gear power recirculating test rig altered tooth-sum gearing scanning electron microscopy (SEM)

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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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The Tong Test: Evaluating Artificial General Intelligence Through Dynamic Embodied Physical and Social

Yujia Peng,Jiaheng Han,Zhenliang Zhang,Lifeng Fan,Tengyu Liu,Siyuan Qi,Xue Feng,Yuxi Ma,Yizhou Wang,Song-Chun Zhu,

《工程（英文）》 doi: 10.1016/j.eng.2023.07.006

摘要： The release of the generative pre-trained transformer (GPT) series has brought artificial general intelligence (AGI) to the forefront of the artificial intelligence (AI) field once again. However, the questions of how to define and evaluate AGI remain unclear. This perspective article proposes that the evaluation of AGI should be rooted in dynamic embodied physical and social interactions (DEPSI). More specifically, we propose five critical characteristics to be considered as AGI benchmarks and suggest the Tong test as an AGI evaluation system. The Tong test describes a value- and ability-oriented testing system that delineates five levels of AGI milestones through a virtual environment with DEPSI, allowing for infinite task generation. We contrast the Tong test with classical AI testing systems in terms of various aspects and propose a systematic evaluation system to promote standardized, quantitative, and objective benchmarks and evaluation of AGI.

关键词： Artificial general intelligence Artificial intelligence benchmark Artificial intelligence evaluation Embodied artificial intelligence Value alignment Turing test Causality

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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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Primary cilia in hard tissue development and diseases

《医学前沿（英文）》 2021年第15卷第5期页码 657-678 doi: 10.1007/s11684-021-0829-6

摘要： Bone and teeth are hard tissues. Hard tissue diseases have a serious effect on human survival and quality of life. Primary cilia are protrusions on the surfaces of cells. As antennas, they are distributed on the membrane surfaces of almost all mammalian cell types and participate in the development of organs and the maintenance of homeostasis. Mutations in cilium-related genes result in a variety of developmental and even lethal diseases. Patients with multiple ciliary gene mutations present overt changes in the skeletal system, suggesting that primary cilia are involved in hard tissue development and reconstruction. Furthermore, primary cilia act as sensors of external stimuli and regulate bone homeostasis. Specifically, substances are trafficked through primary cilia by intraflagellar transport, which affects key signaling pathways during hard tissue development. In this review, we summarize the roles of primary cilia in long bone development and remodeling from two perspectives: primary cilia signaling and sensory mechanisms. In addition, the cilium-related diseases of hard tissue and the manifestations of mutant cilia in the skeleton and teeth are described. We believe that all the findings will help with the intervention and treatment of related hard tissue genetic diseases.

关键词： primary cilia bone mechanical sensing hard tissue cilium-related bone disease tooth

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Mathematical model and manufacture programming of loxodromic-type normal circular-arc spiral bevel gear

Zhenyun DUAN, Houjun CHEN, Zhilan JU, Jian LIU

《机械工程前沿（英文）》 2012年第7卷第3期页码 312-321 doi: 10.1007/s11465-012-0308-5

摘要：

In this paper, loxodromic-type normal circular-arc spiral bevel gear is proposed as a novel application of the circular-arc tooth profile at the gear transmission with intersecting axes. Based on the principle of molding-surface conjugation, the study develops a mathematical model for the tooth alignment curve and the computational flow at the design stage to enable the generation of the tooth surface. Machining of the tooth surface is then carried out to determine the interference-free tool path of the numerical control (NC). Moreover, a pair of loxodromic-type normal circular-arc spiral bevel gears is manufactured on computer numerical control (CNC) machine tools. The proposed theory and method are experimentally investigated, and the obtained results primarily reflect the superior performance of the proposed novel gear.

关键词： loxodrome circular-arc tooth profile Wildhaber-Novikov (W-N) gear spiral bevel gear

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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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预应力梁桥齿板锚固区配筋设计新方法

张向群,林波,刘钊

《中国工程科学》 2010年第12卷第4期页码 82-85

摘要：

预应力混凝土梁桥的齿板锚固区，由于存在着几何形体上的突变，集中锚固力的作用以及预应力钢束局部弯曲引起的径向力作用，易产生开裂甚至剥落破坏，因此齿板锚固区的抗裂配筋设计十分重要。以7种典型局部作用效应刻画齿板锚固区内拉应力的集中分布特征，并在此基础上形成了齿板锚固区拉压杆模型，初步形成预应力混凝土梁桥的抗裂钢筋设计新方法。

关键词：齿板锚固区 D区拉压杆模型

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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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Numerical analysis of nonlinear dynamic behavior of earth dams

Babak EBRAHIMIAN

《结构与土木工程前沿（英文）》 2011年第5卷第1期页码 24-40 doi: 10.1007/s11709-010-0082-6

摘要： A numerical study is conducted to investigate the dynamic behavior of earth dams. The numerical investigation employs a fully nonlinear dynamic finite difference analysis incorporating a simple elastic perfectly plastic constitutive model to describe the stress-strain response of the soil and the Rayleigh damping to increase the level of hysteretic damping. The extended Masing rules are implemented into the constitutive model to explain more accurately the soil response under general cyclic loading. The soil stiffness and hysteretic damping change with loading history. The procedures for calibrating the constructed numerical model with centrifuge test data and also a real case history are explained. For the latter, the Long Valley (LV) earth dam subjected to the 1980 Mammoth Lake earthquake as a real case-history is analyzed and the obtained numerical results are compared with the real measurements at the site in both the time and frequency domains. Relatively good agreement is observed between computed and measured quantities. It seems that the Masing rules combined with a simple elasto-plastic model gives reasonable numerical predictions. Afterwards, a comprehensive parametric study is carried out to identify the effects of dam height, input motion characteristics, soil behavior, strength of the shell materials and dam reservoir condition on the dynamic response of earth dams. Three real earthquake records with different levels and peak acceleration values (PGAs) are used as input motions. The results show that the crest acceleration decreases when the dam height increases and no amplification is observed. Further, more inelastic behavior and more earthquake energy absorption are observed in higher dams.

关键词： earth dam numerical nonlinear response dynamic analysis earthquake dam height

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Construction of interfacial dynamic bonds for high performance lignin/polymer biocomposites

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1372-1388 doi: 10.1007/s11705-023-2302-3

摘要： Lignin is the largest natural aromatic biopolymer, but usually treated as industrial biomass waste. The development of lignin/polymer biocomposites can promote the high value utilization of lignin and the greening of polymers. However, the weak interfacial interaction between industrial lignin and polymer induces poor compatibility and serious agglomeration in polymer owing to the strong intermolecular force of lignin. As such, it is extremely difficult to prepare high performance lignin/polymer biocomposites. Recently, we proposed the strategy of in situ construction of interfacial dynamic bonds in lignin/polymer composites. By taking advantage of the abundant oxygen-containing polar groups of lignin, we inserted dynamic bonding connection such as hydrogen bonds and coordination bonds into the interphase between lignin and the polymer matrix to improve the interfacial interactions. Meanwhile, the natural amphiphilic structure characteristics of lignin were utilized to construct the hierarchical nanophase separation structure in lignin/polymer composites. The persistent problems of poor dispersity and interfacial compatibility of lignin in the polymer matrix were effectively solved. The lignin-modified polymer composites achieved simultaneously enhanced strength and toughness. This concise review systematically summarized the recent research progress of our group toward building high-performance lignin/polymer biocomposites through the design of interfacial dynamic bonds (hydrogen bonds, coordination bonds, and dynamic covalent bonds) between lignin and different polymer systems (polar plastics, rubber, polyurethane, hydrogels, and other polymers). Finally, the future development direction, main challenges, and potential solutions of lignin application in polymers were presented.

关键词： lignin polymer interfacial dynamic bonds

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Molecular size characterization of heavy oil fractions in vacuum and solution by molecular dynamic simulation

Wenpo REN, Honggang CHEN, Chaohe YANG, Honghong SHAN,

《化学科学与工程前沿（英文）》 2010年第4卷第3期页码 250-256 doi: 10.1007/s11705-009-0281-7

摘要： Two kinds of heavy oils were fractionated into eight fractions by Liquid-Solid Adsorption Chromatography, respectively, and samples were collected to measure properties. According to the elemental analysis, molecular weight and H-NMR data, average molecular structures of polycyclic aromatic and heavy resin were constructed with improved Brown-Ladner (B-L) method and several corrections. And then, the most stable conformations of polycyclic aromatic and heavy resin in vacuum and toluene solution were obtained by molecular dynamic simulation, and the molecular size was gotten via the radius of gyration analysis. The results showed that the radius of gyration of polycyclic aromatic and heavy resin was 0.55–0.70 nm in vacuum and 0.60–0.90 nm in toluene solution. With molecular weight increasing, the molecular size in vacuum and toluene solution also increased. Due to the swelling behavior of solvent, the alkyl side chains of heavy oil molecule in solution were more stretched. Thus, the molecular size in toluene solution was larger than that in vacuum.

关键词： dynamic simulation molecular dynamic behavior molecule Adsorption Chromatography