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基于卷积—反残差和组合注意力机制的航天器多余物检测

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计算机集成制造系统 2024年第1期30卷 53-66页

作者：花诗燕李大伟贾书一汪俊南京航空航天大学计算机科学与技术学院江苏南京210001 南京航空航天大学机电学院江苏南京210001

航天器密闭电子设备内腔多余物给航天器飞行安全带来了巨大隐患。由于多余物体积小、与设备内常规组件形态结构相似且易被其他组件遮挡,采用现有的方法对其进行检测时误检、漏检频发。为解决上述问题,提出一种基于卷积—反残差和组合注... 详细信息

航天器密闭电子设备内腔多余物给航天器飞行安全带来了巨大隐患。由于多余物体积小、与设备内常规组件形态结构相似且易被其他组件遮挡,采用现有的方法对其进行检测时误检、漏检频发。为解决上述问题,提出一种基于卷积—反残差和组合注意力机制的航天器密闭电子设备多余物检测网络RPDN。首先,网络通过构建卷积—反残差模块,保证了多余物细粒度特征的完整性;其次,设计组合注意力机制,增强了多余物特征的表征能力;最后,结合多尺度特征融合模块与目标检测层从多维度进行目标预测。实验结果表明RPDN在各项评价指标上均取得了良好的效果,mAP达到92.16%,检测效率达到了13FPS,实现了航天器密闭电子设备内腔多余物高效、精准检测。

关键词：航天器密闭电子设备多余物检测卷积—反残差模块组合注意力机制

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壳聚糖基气凝胶药物控释体系的构建与应用

上海纺织科技 2024年第5期52卷 21-27页

作者：陈迟李珂苏新李大伟张伟付译鋆南通大学纺织服装学院江苏南通226019 安全防护用特种纤维复合材料研发国家地方联合工程研究中心江苏南通226019

药物控释体系能够在特定环境中实现药物靶向释放,稳定药物浓度,减少药物突释引起的毒性。壳聚糖基气凝胶是一类以固体为骨架、气体为分散介质的具有三维多孔网络结构的新型纳米材料,展现出高比表面积、高孔隙率、低密度及优异的生物相... 详细信息

药物控释体系能够在特定环境中实现药物靶向释放,稳定药物浓度,减少药物突释引起的毒性。壳聚糖基气凝胶是一类以固体为骨架、气体为分散介质的具有三维多孔网络结构的新型纳米材料,展现出高比表面积、高孔隙率、低密度及优异的生物相容性等特性,在药物控释领域具有应用前景。结合国内外研究现状,系统综述了壳聚糖基气凝胶药物控释体系的构建方法及载药方法,分析了其性能及其影响因素,阐述了其药物控释机理,探讨了其在慢性创面和癌症治疗方面的应用。最后,对其未来发展方向进行了展望,指出高载药量、可控释药速率及高生物利用度是壳聚糖基气凝胶载药体系未来的发展方向。

关键词：壳聚糖气凝胶药物控释载药冷冻干燥

大数据及人工智能技术在科产金一体化服务中的应用研究

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债券 2024年第5期 18-23页

作者：张炜李世中刘志娟李大伟工业和信息化部产业发展促进中心北京航空航天大学网络空间安全学院

科技与产业创新离不开完善的科技金融体系保障。要做好科技产业金融一体化服务,就要实现金融科技的不断创新,驱动金融体系系统性变革。本文提出了基于人工智能与大数据技术的科产金一体化服务支撑体系,通过数据收集、模型建立与决策输出... 详细信息

科技与产业创新离不开完善的科技金融体系保障。要做好科技产业金融一体化服务,就要实现金融科技的不断创新,驱动金融体系系统性变革。本文提出了基于人工智能与大数据技术的科产金一体化服务支撑体系,通过数据收集、模型建立与决策输出,帮助金融机构挖掘数据价值,推动运营效率提升和业态创新,更好支持科技创新与产业升级转型。

关键词：科技产业金融一体化科技金融大数据人工智能科技创新

Improved Hybrid Method to Calculate Inductances of Permanent Magnet Synchronous Machines with Skewed Stators Based on Winding Function Theory

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Chinese Journal of Electrical Engineering 2016年第1期2卷 52-61页

作者： Yuting Gao Ronghai Qu dawei li State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

An improved hybrid method combining two dimensional(2D)finite element analysis(FEA)and the analytical method is put forward to calculate the stator winding inductance and synchronous inductance influenced by stator skewing *** on winding function theory(WFT),the improved method proposes two factors to describe variable inductances along the stator skewing *** simulations are then performed on three interior permanent magnet synchronous machines(IPMSMs),one normal and two skewed machines(half slot and one slot pitch skewing respectively).Extensive experiments are conducted on relevant prototypes with good ***,analysis and comparisons are made as to the influence of different skewing angles on the inductances and torque-speed *** is found that Ld increases and Lq decreases by skewing,leading to the reduction of the rotor saliency and maximal torque capability,but increase of the flux weakening capability.

关键词： Finite element analysis(FEA) inductances permanent magnet synchronous machine(PMSM) skewing winding function theory(WFT).

CO2/NIR light dual-controlled nanoparticles for dsDNA unzipping

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Chinese Chemical Letters 2020年第1期31卷 281-284页

作者： Yanjing Wang Hongbo Yuan dawei li Chengfen Xing Key Laboratory of Hebei Province for Molecular Biophysics Institute of BiophysicsHebei University of TechnologyTianjin 300401China Institute of Polymer Science and Engineering College of Chemical Engineering Hebei University of TechnologyTianjin 300130China

Both of carbon dioxide(CO2)and near-infrared(NIR)light as triggers for non-invasive remotely control are attracting wide attentions due to their good biocompatibility and easy ***,CO2/NIR light dual controlled nanoparticles are proposed to remotely regulate the unzipping of dsDNA by using imidazole functionalized conjugated polymer nanoparticles(imidazole-CPNs).The dsDNA successfully coats on the shell of imidazole-CPNs to form imidazole-CPNs/dsDNA assembly due to intensively electrostatic interaction triggered by ***,the unzipping process of dsDNA is remotely controlled by NIR light based on the photothermal effect,and it can be readily monitored by the fluorescence intensity of ethidium bromide(EB)and CD spectra of ***,dual stimulation responsive imidazole-CPNs effectively control dsDNA unzipping under CO2 stimulus and NIR light,promising a new direction in the biological applications of DNA,such as the treatments of diseases caused by gene duplication abnormality.

关键词： Carbon dioxide Conjugated polymers nanoparticles Photothermal effect dsDNA Near-infrared light

Revocable Hierarchical Identity-Based Broadcast Encryption

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Tsinghua Science and Technology 2018年第5期23卷 539-549页

作者： dawei li Jianwei liu Zongyang Zhang Qianhong Wu Weiran liu School of Electronic and Information Engineering Beihang University Beijing 100191 China

Hierarchical Identity-Based Broadcast Encryption （HIBBE） organizes users into a tree-like structure, and it allows users to delegate their decryption ability to subordinates and enable encryption to any subset of users while only intended users can decrypt. However, current HIBBE schemes do not support efficient revocation of private keys. Here, a new primitive called Revocable Hierarchical Identity-Based Broadcast Encryption （RHIBBE） is formalized that allows revocation of the HIBBE. Ciphertext indistinguishability is defined against the selectively Bounded Revocable Identity-Vector-Set and Chosen-Plaintext Attack （IND-sBRIVS-CPA）. An IND-sBRIVS-CPA secure RHIBBE scheme is constructed with efficient revocation on prime-order bilinear groups. The unbounded version of the scheme is also shown to be secure but a little weaker than the former under the decisional n-Weak Bilinear Diffie-Hellman inversion assumption.

关键词： Revocable Hierarchical Identity-Based Broadcast Encryption (RHIBBE) revocation provable security

Rapid method for on-site determination of phenolic contaminants in water using a disposable biosensor

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Frontiers of Environmental Science & Engineering 2012年第6期6卷 831-838页

作者： Yuanting li dawei li Wei SONG Meng li Jie ZOU Yitao LONG Key Laboratory for Advanced Materials&Department of Chemistry East China University of Science and TechnologyShanghai 200237China Jiangsu Provincial Supervising&Testing Research Institute for Products Quality Nanjing 210007China

A disposable biosensor was fabricated using single-walled carbon nanotubes, gold nanoparticles and tyrosinase （SWCNTs-AuNPs-Tyr） modified screen-printed electrodes. The prepared biosensor was applied to the rapid determination of phenolic contaminants within 15 minutes. The SWCNTs-AuNPs-Tyr bionanocomposite sensing layer was characterized with scanning electron micro- scopy, electrochemical impedance spectroscopy and cyclic voltammetry methods. The characterization results revealed that SWCNTs could lead to a high loading of tyrosinase （Tyr） with the large surface area and the porous morphology, while AuNPs could retain the bioactivity of Tyr and enhance the sensitivity. The detection conditions, including working potential, pH of supporting electrolyte and the amount of Tyr were optimumed. As an example, the biosensor for catechol determination displayed a linear range of 8.0 × 10^-8 to 2.0 × 10^- 5 mol.L-1 with a detection limit of 4.5 × 10^-8 mol.L-1 （S/N= 3）. This method has a rapid response time within 10 s, and shows excellent repeatability and stability. Moreover, the resulting biosen- sor could be disposable, low-cost, reliable and easy to carry. This kind of new Tyr biosensor provides great potential for rapid, on-site and cost-effective analysis of phenolic contaminants in environmental water samples.

关键词： on-site determination tyrosinase biosensor,phenolic contaminants single-walled carbon nanotubes,gold nanoparticles screen-printed electrodes

Variable Stiffness Identification and Configuration Optimization of Industrial Robots for Machining Tasks

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Chinese Journal of Mechanical Engineering 2022年第5期35卷 275-290页

作者： Jiachen Jiao Wei Tian lin Zhang Bo li Junshan Hu Yufei li dawei li Jianlong Zhang Nanjing University of Aeronautics and Astronautics Nanjing 210016China Beijing Institute of Space Launch Technology Beijing 100076China Beijing Institute of Mechanical Equipment Beijing 100854China

Industrial robots are increasingly being used in machining tasks because of their high flexibility and ***,the low structural stiffness of a robot significantly affects its positional accuracy and the machining quality of its operation *** robot stiffness characteristics and optimization methods is an effective method of improving the stiffness performance of a ***,aiming at the poor accuracy of stiffness modeling caused by approximating the stiffness of each joint as a constant,a variable stiffness identification method is proposed based on space ***,a task-oriented axial stiffness evaluation index is proposed to quantitatively assess the stiffness performance in the machining *** addition,by analyzing the redundant kinematic characteristics of the robot machining system,a configuration optimization method is further developed to maximize the *** numerous points or trajectory-processing tasks,a configuration smoothing strategy is proposed to rapidly acquire optimized ***,experiments on a KR500 robot were conducted to verify the feasibility and validity of the proposed stiffness identification and configuration optimization methods.

关键词： Industrial robot Space gridding Variable stiffness identification Configuration optimization Smooth processing

多壁碳纳米管/聚苯胺纳米纤维复合材料的制备及其吸附性能研究

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化工新型材料 2024年第2期52卷 120-124,129页

作者：王超然陶玉仑李大为吴远楠吕胤儒安徽理工大学材料科学与工程学院淮南232001

为了探究掺杂后聚苯胺(PANI)吸附染料的性能,以有机酸、多壁碳纳米管(MWCNTs)为掺杂剂,过硫酸铵为氧化剂,通过原位氧化聚合法合成了多壁碳纳米管/聚苯胺(MWCNTs/PANI)纳米纤维复合材料,利用紫外-可见光分光光度计、傅里叶变换红外光谱仪... 详细信息

为了探究掺杂后聚苯胺(PANI)吸附染料的性能,以有机酸、多壁碳纳米管(MWCNTs)为掺杂剂,过硫酸铵为氧化剂,通过原位氧化聚合法合成了多壁碳纳米管/聚苯胺(MWCNTs/PANI)纳米纤维复合材料,利用紫外-可见光分光光度计、傅里叶变换红外光谱仪、X射线衍射仪、扫描电子显微镜对其结构、组成及微观形貌进行表征。使用MWCNTs/PANI纳米纤维复合材料和PANI对刚果红溶液进行吸附实验,发现复合材料吸附效果更优异,吸附率达到95%左右。通过吸附动力学研究复合材料的吸附机理,结果表明MWCNTs/PANI纳米纤维复合材料吸附刚果红的过程符合准二级动力学模型。

关键词：聚苯胺多壁碳纳米管复合材料吸附动力学