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Chinese Journal of Aeronautics 2024年第9期37卷 369-384页

作者： Xiaofeng LI Jian TIAN Cheng WEI xibin CAO School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing Instiuteof Spacecraft System Engineering China Academy of Space TechnolgyBeijing 100094Chia

With the rapid development of space activities,non-cooperative space targets increase swiftly,such as failed satellites and upper stages,threating normal spacecrafts *** there are some problems in the capture process,such as excessive collision and fast tumbling of targets,manipulator with redundant Degrees of Freedom(DOFs)can be used to improve the compliance and therefore solve these *** Rope-Driven Snake Manipulator(RDSM)is a combina-tion of hyper-redundant DOFs and better compliance,and therefore it is suitable for capturing *** this paper,a snake manipulator mechanism is designed,and the complete kinematic model and system dynamic model considering RDSM,target and contact is ***,to obtain the configuration of joint with hyper-redundant DOFs,an improved motion dexterity index is pro-posed as the joint motion optimization ***,the force-position collaborative optimization index is designed to adjust active stiffness,and the impedance control method based on the modified index is used to capture the space ***,the proposed force-position collaborative opti-mization method is verified by virtual prototype *** results demonstrate that based on the proposed method,the collision force is reduced by about 2.%compared to normal impe-dance control,showing higher safety.

关键词： Capturing non-cooperative spacetargets Rope-driven snakemanipu-lator Force-position collaborative optimization Redundant degrees of free-dom Active stiffness adjustment

Satellite anomaly detection based on reconstruction discrepancy theory utilizing a new dual-branch reconstruction model

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Science China Technological Sciences 2024年第10期67卷 3294-3307页

作者： ZHAO HaoTian QIU Shi LIU Ming CAO xibin Research Center of Satellite Technology School of AstronauticsHarbin Institute of Technology

To enhance the accuracy of deep learning methods based on reconstruction discrepancy in satellite anomaly detection tasks, this study proposes a dual-branch reconstruction model(DBRM) and designs a comprehensive satellite anomaly detection framework around this model. Firstly, we introduce the temporal-channel mixer(TC-Mixer) module, which mainly comprises a self-attention layer for capturing long-range temporal dependencies in telemetry data, and two types of feed-forward networks(FFN) for extracting complex patterns in the temporal and channel dimension of telemetry data. This design endows the TC-Mixer module with robust capabilities for extracting complicated dependencies in telemetry data. Secondly, with the TC-Mixer module as the main component, we designed the DBRM. This model utilizes a shared latent representation layer, allowing the regeneration branch and forecasting branch of the DBRM to share most of the feature extraction network architecture. This approach significantly enhances the model's regression accuracy while reducing computational complexity. Thirdly, using the DBRM as the core network model, we devised a comprehensive satellite anomaly detection framework. This includes an anomaly criterion that considers the reconstruction discrepancy of both the regeneration and forecasting branches, the peak-over-threshold(POT) method for anomaly thresholding, and the MIC-based feature engineering method, etc. Finally, we conducted comparative experiments with several SOTA anomaly detection algorithms on two public and one private satellite anomaly detection datasets. The experimental results validate the effectiveness and superiority of our proposed method.

关键词： anomaly detection reconstruction discrepancy dual-branch reconstruction model (DBRM) satellite telemetry data time series

Early chatter identification based on optimized VMD with multi-band information fusion and compression method in robotic milling process

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Chinese Journal of Aeronautics 2024年第6期37卷 464-484页

作者： Sichen CHEN Zhiqiang LIANG Yuchao DU Zirui GAO Haoran ZHENG Zhibing LIU Tianyang QIU xibin WANG School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Undesirable self-excited chatter has always been a typical issue restricting the improvement of robotic milling quality and *** chatter identification based on processing signals can prompt operators to adjust the machining process and prevent chatter *** with the traditional machine tool,the uncertain multiple chatter frequency bands and the band-moving of the chatter frequency in robotic milling process make it more challenging to extract chatter *** paper proposes a novel method of chatter identification using optimized variational mode decomposition(OVMD)with multi-band information fusion and compression technology(MT).During the robotic milling process,the number of decomposed modes k and the penalty coefficient a are optimized based on the dominant component of frequency scope partition and fitness of the mode center ***,the mayfly optimization algorithm(MA)is employed to obtain the global optimal parameter *** order to conquer information collection about the uncertain multiple chatter frequency bands and the band-moving of the chatter frequency in robotic milling process,MT is presented to reduce computation and extract signal ***,the cross entropy of the image(CEI)is proposed as the final chatter indicator to identify the chatter *** robotic milling experiments are carried out to verify the proposed method,and the results show that it can distinguish the robotic milling condition by extracting the uncertain multiple chatter frequency bands and overcome the band-moving of the chatter frequency in robotic milling process.

关键词： Robotic milling Chatter detection Variational mode decomposition Information fusion and compression Chatter featur

A Transparent Photoresist Made of Titanium Dioxide Nanoparticle-Embedded Acrylic Resin with a Tunable Refractive Index for UV-Imprint Lithography

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Engineering 2024年第6期37卷 96-104页

作者： Yinglu Liu Dan Wang Changlin Liu Qianqian Hao Jian Li Jie-Xin Wang Xiuyun Chen Peng Zhong xibin Shao Jian-Feng Chen State Key Laboratory of Organic–Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China BOE Technology Group Co. Ltd.Beijing 100176China

Transparent photoresists with a high refractive index(RI)and high transmittance in visible wavelengths have promising functionalities in optical *** work reports a kind of tunable optical material composed of titanium dioxide nanoparticles embedded in acrylic resin with a high RI for ultraviolet(UV)-imprint *** hybrid film exhibits a tunable RI of up to 1.67(589 nm)after being cured by UV light,while maintaining both a high transparency of over 98%in the visible light range and a low haze of less than 0.05%.The precision machining of optical microstructures can be imprinted easily and efficiently using the hybrid resin,which acts as a light guide plate(LGP)to guide the light from the side to the top in order to conserve the energy of the display *** preliminary studies based on both laboratory and commercial experiments pave the way for exploiting the unparalleled optical properties of nanocomposite resins and promoting their industrial application.

关键词： Photoresist Tunable refractive index Hanson solubility Ultraviolet imprint Organic-inorganic composites

Mode-insensitive and mode-selective optical switch based on asymmetric Y-junctions and MMI couplers

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Photonics Research 2024年第3期12卷 423-430页

作者： SHIJIE SUN QIDONG YU YUANHUA CHE TIANHANG LIAN YUHANG XIE DAMING ZHANG xibin WANG State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

Driven by the large volume demands of data in transmission systems,the number of spatial modes supported by mode-division multiplexing(MDM)systems is being increased to take full advantage of the parallelism of the signals in different spatial *** a key element for photonic integrated circuits,the multimode waveguide optical switch(MWOS)is playing an important role for data exchange and signal ***,the function of the traditional MWOS is simple,which could only implement the mode-insensitive or mode-selective switching function;it is also difficult to scale to accommodate more spatial modes because of the limitation of the device ***,it is still challenging to realize a multifunctional and scalable MWOS that could support multiple modes with low power consumption and high ***,we propose and experimentally demonstrate a multifunctional MWOS based on asymmetric Y-junctions and multimode interference(MMI)couplers fabricated on a polymer waveguide *** mode-insensitive and mode-selective switching functions can be achieved via selectively heating different electrode *** fabricated device with the total length of∼0.8 cmshows an insertion loss of less than 12.1 dB,and an extinction ratio of larger than 8.4 dB with a power consumption of∼32.mW for both mode-insensitive and mode-selective switching functions,at 1550 nm *** proposed MWOS can also be scaled to accommodate more spatial modes flexibly and easily,which can serve as an important building block for MDM systems.

关键词： waveguide optical mode

电影《摔跤吧!爸爸》关于女性体育发展的反思与启示:社会性别视角

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成都体育学院学报 2024年第3期50卷 127-133页

作者：高希彬上海体育大学体育教育学院上海200438

基于社会性别相关理论,探讨影片《摔跤吧!爸爸》所引发的女性体育发展的困境与出路。得出如下结论:大众传统的性别观念、家庭刻板的性别印象、学校异化的性别环境、个体的性别角色冲突是女性体育发展的限制性因素;主观体验、成就信念、... 详细信息

基于社会性别相关理论,探讨影片《摔跤吧!爸爸》所引发的女性体育发展的困境与出路。得出如下结论:大众传统的性别观念、家庭刻板的性别印象、学校异化的性别环境、个体的性别角色冲突是女性体育发展的限制性因素;主观体验、成就信念、自我尊重、自主动机是女性体育发展的激励性因素。建议:从性别平等的角度改变一贯、传统、刻板的社会性别观念,给予女性体育参与者(爱好者)更多的支持、认同、理解,可让女性体育从参与到坚持,最终走上可持续性的发展之路。研究可为我国女性体育发展提供一定的借鉴与启示。

关键词：《摔跤吧!爸爸》女性体育性别社会性别体育电影

耐盐碱性蛋白酶菌株LK-3的筛选及酶学性质

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食品与生物技术学报 2024年第3期43卷 46-53页

作者：刘可玉宁喜斌上海海洋大学食品学院上海201306 上海水产品加工及贮藏工程技术研究中心上海201306 农业农村部水产品贮藏保鲜质量安全风险评估试验室(上海) 上海201306 国家淡水水产品加工技术研发分中心(上海) 上海201306

为了寻找产碱性蛋白酶活性高且稳定性良好的野生菌株,作者从上海临港区域的东海海水中筛选出一株高产稳定且耐盐的产碱性蛋白酶菌株。对该菌株的形态学特性、生理特性以及16S rDNA基因序列进行测序和分析,确定该菌株为同温层芽孢杆菌(Ba... 详细信息

为了寻找产碱性蛋白酶活性高且稳定性良好的野生菌株,作者从上海临港区域的东海海水中筛选出一株高产稳定且耐盐的产碱性蛋白酶菌株。对该菌株的形态学特性、生理特性以及16S rDNA基因序列进行测序和分析,确定该菌株为同温层芽孢杆菌(Bacillus stratosphericus),并命名为B. stratosphericus LK-3。酶学性质研究结果显示,该酶的最适作用条件为温度35℃、p H 8.5、最适接种体积分数7%,该酶在上述条件下发酵72.h的酶活力为(581.74±0.81) U/mL。此外该酶具有较好的耐盐性,即使在40 g/dL的高饱和盐质量浓度下仍然保持2..03%的相对原始酶活力。蛋白酶的耐盐性是一个有价值的特性,可将其纯化后作为洗涤剂的生物添加剂应用于工业生产。

关键词：碱性蛋白酶菌株LK-3筛选同温层芽孢杆菌酶学性质耐盐菌

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生成式人工智能重塑科技期刊产业的影响、挑战及应对策略研究

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中国科技期刊研究 2024年第7期35卷 890-898页

作者：陈晓峰沈锡宾湖北省科技信息研究院《科技进步与对策》编辑部湖北武汉430071 武汉理工大学计算机与人工智能学院湖北武汉430070 中华医学会杂志社新媒体部北京100052 国家新闻出版署医学期刊知识挖掘与服务重点实验室北京100052

【目的】探讨生成式人工智能给科技期刊业带来的影响与挑战,分析不同利益相关者的诉求与风险,提出科技期刊业应对生成式人工智能挑战的关键举措。【方法】基于文献综述梳理生成式人工智能在科技期刊业应用的最新进展,构建“需求—风险... 详细信息

【目的】探讨生成式人工智能给科技期刊业带来的影响与挑战,分析不同利益相关者的诉求与风险,提出科技期刊业应对生成式人工智能挑战的关键举措。【方法】基于文献综述梳理生成式人工智能在科技期刊业应用的最新进展,构建“需求—风险”二维分析框架,对不同应用场景进行分类评估;采用利益相关者分析法,多维解构生成式人工智能对作者、编辑、审稿人、读者等主体的影响;借鉴国内外经验教训,从前瞻政策、技术创新、服务升级、人才培养、伦理治理等方面系统提出推进科技期刊业智能化转型的对策建议。【结果】当前生成式人工智能已广泛应用于科技期刊选题策划、学术写作、同行评议、编辑出版、学术传播等环节,极大提升行业智能化水平,但也带来内容同质化、学术造假等问题隐患。不同利益相关者对生成式人工智能的诉求各异,既有效率提升、成本节约等普遍需求,也面临版权侵权、职业替代、伦理失范等风险挑战。【结论】生成式人工智能正驱动科技期刊业态重塑,亟须统筹布局、多管齐下,在加快关键技术创新应用的同时,注重人才培养和伦理规范,促进人机协同,构建开放共享、合作共赢的融合发展新生态,推动行业创新发展。

关键词：生成式人工智能科技期刊产业融合发展应用场景应对策略

异常行为敏感的学生行为时序建模及心理健康预测方法

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北京工业大学学报 2024年第8期50卷 939-947页

作者：贾熹滨魏心岚北京工业大学信息学部北京100124

为了对学生异常行为的早期感知及校园行为时序建模,提出一种异常行为敏感的学生行为时序建模及心理健康预测(student behavioral temporal modeling sensitive to abnormal behavior for mental health prediction, SBTM-SABMHP)方法,利用移动设备收集的加速器、声音传感器及移动热点(wireless fidelity, WI-FI)等多种行为感知数据,构建异质信息网络,对学生当前行为模式进行建模。同时,为实现对学生历史行为时序数据的建模,建立了基于注意力机制的异常行为敏感的门控模块,有效融合学生长短期行为,并对学生行为时序建模,实现心理健康预测。在公共数据集StudentLife上对所提出的模型进行了对比分析实验。实验结果表明,与多种学生心理健康预测基线方法相比,该方法在4个评价指标上都取得了最佳性能,证明了该模型在学生心理健康预测任务上的有效性。

关键词：学生行为建模异质信息网络注意力机制门控机制教育数据挖掘心理健康预测

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基于二阶全驱系统的航天器姿态避障控制

航空学报 2024年第1期45卷 94-102页

作者：鲁明陈雪芹吴凡曹喜滨哈尔滨工业大学卫星技术研究所哈尔滨150001

针对航天器大角度姿态机动任务,考虑存在姿态禁止区域和干扰力矩影响,提出一种基于全驱系统模型的姿态机动控制方法。基于三维特殊正交群直接描述姿态运动并基于其李代数——指数坐标建立了误差姿态二阶全驱模型;提出基于三维特殊正交... 详细信息

针对航天器大角度姿态机动任务,考虑存在姿态禁止区域和干扰力矩影响,提出一种基于全驱系统模型的姿态机动控制方法。基于三维特殊正交群直接描述姿态运动并基于其李代数——指数坐标建立了误差姿态二阶全驱模型;提出基于三维特殊正交群的障碍李雅普诺夫函数,保证在其有界情况下姿态约束得到遵守;最后提出包含障碍李雅普诺夫函数的总李雅普诺夫函数,使用滑模技术并结合二阶全驱模型中参数矩阵的性质消除导数中的非线性项得到简洁的控制律。数值仿真结果显示,在所提出的控制方法作用下,航天器能够避开姿态禁止区域并收敛于期望姿态,并且稳态误差和控制能耗相比现有同类方法表现优异。

关键词：全驱系统李群指数坐标姿态机动控制障碍李雅普诺夫函数