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Construction of smart propellant with multi-morphologies

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Defence Technology（防务技术） 2024年第3期33卷 180-185页

作者： Weitao Yang yuchen Gao Rui Hu Manman Li Fengqi Zhao He jiang Xuan Zhang Xi’an Modern Chemistry Research Institute Xi’an710065China Northwestern Polytechnical University Xi’an710072China

Smart materials,which exhibit shape memory behavior in response to external stimuli,have shown great potential for use in biomedical applications.In this study,an energetic composite was fabricated using a UV-assisted DIW 3D printing technique and a shape memory material(SMP)as the binder.This composite has the ability to reduce the impact of external factors and adjust gun propellant combustion behavior.The composition and 3D printing process were delineated,while the internal structure and shape memory performance of the composite material were studied.The energetic SMP composite exhibits an angle of reversal of 18 s at 70°,with a maximum elongation typically reaching up to 280% of the original length and a recovery length of approximately 105%during ten cycles.Additionally,thermal decomposition and combustion behavior were also demonstrated for the energetic SMP composite.

关键词： Smart material Gun propellants Multi-morphologies Self-regulation

Subspace Identification for Closed-Loop Systems With Unknown Deterministic Disturbances

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IEEE/CAA Journal of Automatica Sinica 2023年第12期10卷 2248-2257页

作者： Kuan Li Hao Luo yuchen jiang Dejia Tang Hongyan Yang IEEE Shanghai Aerospace Control Technology Institute Shanghai 201109China the Control and Simulation Center School of AstronauticsHarbin Institute of TechnologyHarbin 150006China the Faculty of Information Technology Engineering Research Center of Digital CommunityMinistry of EducationBeijing University of TechnologyBeijing 100124China

This paper presents a subspace identification method for closed-loop systems with unknown deterministic disturbances.To deal with the unknown deterministic disturbances,two strategies are implemented to construct the row space that can be used to approximately represent the unknown deterministic disturbances using the trigonometric functions or Bernstein polynomials depending on whether the disturbance frequencies are known.For closed-loop identification,CCF-N4SID is extended to the case with unknown deterministic disturbances using the oblique projection.In addition,a proper Bernstein polynomial order can be determined using the Akaike information criterion(AIC)or the Bayesian information criterion(BIC).Numerical simulation results demonstrate the effectiveness of the proposed identification method for both periodic and aperiodic deterministic disturbances.

关键词： Bernstein polynomial closed-loop system subspace identification unknown deterministic disturbances

Enhancement of CH_(3)CO^(*) adsorption by editing d-orbital states of Pd to boost C–C bond cleavage of ethanol eletrooxidation

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Science China Chemistry 2024年第2期67卷 696-704页

作者： yuchen Qin Fengqi Wang Pei Liu Jinyu Ye Qian Wang Yao Wang Guangce jiang Lijie Liu Pengfang Zhang Xiaobiao Liu Xin Zheng Yunlai Ren Junjun Li Zhicheng Zhang College of Sciences Henan Agricultural UniversityZhengzhou450000China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin University&Collaborative Innovation Center of Chemical Science and EngineeringTianjin300072China College of Chemistry and Chemical Engineering Xiamen UniversityXiamen361005China Department of Analysis Sinopec Engineering Group Luoyang R&D Center of TechnologyLuoyang471000China School of Chemical and Material Engineering Jiangnan UniversityWuxi214211China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology Liaocheng UniversityLiaocheng252000China

Improving the complete ethanol electrooxidation on Pd-based catalysts in alkaline media has drawn widely attention due to the high mass energy density.However,the weak adsorption energy of CH_(3)CO^(*) on Pd restricts the C–C bond cleavage.Inspired by the molecular orbital theory,we proposed the d-state-editing strategy to construct more unoccupied d-states of Pd for the enhanced interaction with CH_(3)CO^(*) to break C–C bonds.As expected,the reduced number of e_g electrons and more unoccupied d-states of Pd successfully formed on as-prepared porous Rh Au–Pd Cu nanosheets(PNSs).Theoretical calculations show that the optimized d-states of Rh Au–Pd Cu PNS can effectively improve the adsorption of CH_(3)CO^(*) and drastically reduce the energy barrier of C–C bond cleavage,thus boosting the complete oxidation of ethanol.The charge ratio of C_1 pathway on Rh Au–Pd Cu PNSs is 51.5%,more than 2 times higher than that of Pd NSs.Our finding provides an innovative perspective for the design of highly-efficient noble-based electrocatalysts.

关键词： C–C bond cleavage CH_(3)CO^(*)adsorption unoccupied d-states ethanol oxidation reaction RhAu–PdCu porous nanosheets

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用于学习和解释行人预期行为的群体交互场

Engineering 2024年第3期34卷 70-82页

作者： Xueyang Wang Xuecheng Chen Puhua jiang Haozhe Lin Xiaoyun Yuan Mengqi Ji yuchen Guo Ruqi Huang Lu Fang Sigma Laboratory Department of Electronic EngineeringTsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China Tsinghua Shenzhen International Graduate School Shenzhen 518055China Department of Automation Tsinghua UniversityBeijing 100084China Institute of Artificial Intelligence Beihang UniversityBeijing 100191China Zhejiang Future Technology Institute Yangtze Delta Region Institute of Tsinghua UniversityZhejiangJiaxing 314033China

Anticipating others’actions is innate and essential in order for humans to navigate and interact well with others in dense crowds.This ability is urgently required for unmanned systems such as service robots and self-driving cars.However,existing solutions struggle to predict pedestrian anticipation accurately,because the influence of group-related social behaviors has not been well considered.While group relationships and group interactions are ubiquitous and significantly influence pedestrian anticipation,their influence is diverse and subtle,making it difficult to explicitly quantify.Here,we propose the group interaction field(GIF),a novel group-aware representation that quantifies pedestrian anticipation into a probability field of pedestrians’future locations and attention orientations.An end-to-end neural network,GIFNet,is tailored to estimate the GIF from explicit multidimensional *** quantifies the influence of group behaviors by formulating a group interaction graph with propagation and graph attention that is adaptive to the group size and dynamic interaction states.The experimental results show that the GIF effectively represents the change in pedestrians’anticipation under the prominent impact of group behaviors and accurately predicts pedestrians’future states.Moreover,the GIF contributes to explaining various predictions of pedestrians’behavior in different social states.The proposed GIF will eventually be able to allow unmanned systems to work in a human-like manner and comply with social norms,thereby promoting harmonious human-machine relationships.

关键词： Human behavior modeling and prediction Implicit representation of pedestrian anticipation Group interaction Graph neural network

重载变速冲击工况下MoDDP/CaB复合润滑油添加剂的润滑性能

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中国表面工程 2024年第2期37卷 248-259页

作者：王小勇张慧峰郭佳毫姜宇姜雨辰陕西小保当矿业有限公司榆林719000 中煤科工机器人科技有限公司深圳518052 中国矿业大学机电工程学院徐州221116

为解决机械设备在恶劣工况下由润滑失效而导致的设备故障甚至安全生产事故问题,进一步提升机械设备的运行稳定性和安全性,研究纳米硼酸钙(CaB)和二烷基二硫代磷酸钼(MoDDP)单一润滑油添加剂和复合润滑油添加剂的减摩抗磨效果,并探究其... 详细信息

为解决机械设备在恶劣工况下由润滑失效而导致的设备故障甚至安全生产事故问题,进一步提升机械设备的运行稳定性和安全性,研究纳米硼酸钙(CaB)和二烷基二硫代磷酸钼(MoDDP)单一润滑油添加剂和复合润滑油添加剂的减摩抗磨效果,并探究其润滑作用机制。研究结果表明,重载、变速、冲击工况条件下1.5 wt.%MoDDP/3.0 wt.%CaB复合润滑油添加剂具有良好的减摩抗磨效果,与基础油相比,在不同转速下可最大降低65.1%的摩擦因数和80%的磨痕深度,施加50 N冲击载荷时,可分别降低66.7%的摩擦因数和76.5%的磨痕深度。MoDDP/CaB复合润滑油添加剂在润滑过程中能生成包含C-C、Fe_(2)O_(3)、FeB和MoS_(2)的金属化合物层,添加剂中的CaB和MoDDP能够相互促进彼此反应,增加FeB/MoS_(2)润滑膜的生成量,对比单一的添加剂和基础油,复合添加剂具有更好的自修复性能和协同功效,形成具有高承载力的润滑油膜,提高了复合润滑油的抗磨减摩性能。MoDDP/CaB复合润滑油添加剂的制备可以充分综合利用抗氧化剂与极压耐磨剂的稳定、优异润滑特性,研究结果可为复合添加剂的广泛应用提供数据支持和理论支撑。

关键词： MoDDP/CaB复合润滑油添加剂减摩抗磨变速、重载、冲击

多风电场支撑电网频率稳定的动态差异化时序协同控制策略

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电力系统自动化 2024年第8期48卷 162-173页

作者：姜涛邱宇琛刘先超李国庆现代电力系统仿真控制与绿色电能新技术教育部重点实验室(东北电力大学) 吉林省吉林市132012

针对大规模风电接入带来的系统调频能力不足和调频能量透支引发的频率二次跌落问题,提出一种多风电场动态差异化时序协同的频率支撑控制策略。首先,阐述综合惯量控制下的风电调频原理,基于能量守恒理论分析频率响应阶段风电场群的动能... 详细信息

针对大规模风电接入带来的系统调频能力不足和调频能量透支引发的频率二次跌落问题,提出一种多风电场动态差异化时序协同的频率支撑控制策略。首先,阐述综合惯量控制下的风电调频原理,基于能量守恒理论分析频率响应阶段风电场群的动能变化过程,揭示多风电场调频时序对调频效果的影响机理。然后,考虑多风电场群同时调频引发的频率二次跌落风险,从场站交互视角逆向设计风电场群调频时序和任务分工,并依据风电实时调频能力动态调整投入顺序,以保证初期过程惯量安全需求,并提升频率最低点、抑制风电场群退出调频导致的系统频率严重二次跌落。最后,通过3机9节点测试系统和某实际电网算例对所提控制策略进行仿真分析,结果验证了所提策略的有效性和实用性。

关键词：多风电场动态差异化时序惯量协同控制调频二次跌落

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阿司匹林抗肿瘤活性研究进展

现代肿瘤医学 2024年第9期32卷 1716-1720页

作者：江雨晨香港中文大学公共卫生及基层医疗学院中国香港999077

临床和流行病学研究表明,定期和长期服用低剂量阿司匹林(aspirin,ASA)可降低食管鳞状细胞癌、腺癌等胃肠道癌症的发生风险。ASA已成为一种具有潜力的化学预防肿瘤的药物,肿瘤治疗后使用ASA会提高长期生存率。本文主要通过对与肿瘤相关... 详细信息

临床和流行病学研究表明,定期和长期服用低剂量阿司匹林(aspirin,ASA)可降低食管鳞状细胞癌、腺癌等胃肠道癌症的发生风险。ASA已成为一种具有潜力的化学预防肿瘤的药物,肿瘤治疗后使用ASA会提高长期生存率。本文主要通过对与肿瘤相关生物标志物如环氧合酶(cyclooxygenase,COX)、哺乳动物雷帕霉素靶蛋白(mammalian rapamycin target protein,mTOR)、磷脂酰肌醇3-激酶催化亚基ɑ(phosphatidylinositol 3-kinaseɑ,PIK3CA)等研究,探讨ASA在抗肿瘤活性方面的最新进展,为进一步发挥ASA在抗肿瘤活性中的作用提供新思路、新方案。

关键词： ASA 抗肿瘤活性预防与治疗

基于人工智能的H-E染色全切片病理学图像分析在肺癌研究中的进展

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中国癌症杂志 2024年第3期34卷 306-315页

作者：姜梦琦(综述) 韩昱晨(审校) 傅小龙(审校) 上海市胸科医院/上海交通大学医学院附属胸科医院放疗科上海200030 上海市胸科医院/上海交通大学医学院附属胸科医院病理科上海200030

病理学是疾病诊断的金标准。利用全切片扫描技术将病理切片转化为数字图像后,人工智能特别是深度学习模型在病理学图像分析领域展现出了巨大潜力。人工智能在肺癌全切片扫描中的应用涉及组织病理学分型、肿瘤微环境分析、疗效及生存预... 详细信息

病理学是疾病诊断的金标准。利用全切片扫描技术将病理切片转化为数字图像后,人工智能特别是深度学习模型在病理学图像分析领域展现出了巨大潜力。人工智能在肺癌全切片扫描中的应用涉及组织病理学分型、肿瘤微环境分析、疗效及生存预测等多个方面,有望辅助临床进行精准治疗决策。然而标注数据不足、切片质量差异等因素也限制了病理学图像分析的发展。本文总结了肺癌领域利用人工智能手段进行病理学图像分析的应用进展,并对未来发展方向进行展望。

关键词：全切片扫描肺癌人工智能卷积神经网络

北京市通州区中小学生家庭食物环境健康水平及相关因素

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中国学校卫生 2024年第5期45卷 665-668页

作者：江南雷宇宸吴燕芳孙文韬北京市通州区疾病预防控制中心营养与食品卫生科 101100

目的了解通州区中小学生家庭食物环境健康水平及其相关因素,为开展通州区中小学生家庭食物环境提升工作提供参考。方法于2021—2023年采用分层整群抽样方法,对通州区11所学校的1485个学生家庭进行问卷调查。采用单因素分析比较不同人口... 详细信息

目的了解通州区中小学生家庭食物环境健康水平及其相关因素,为开展通州区中小学生家庭食物环境提升工作提供参考。方法于2021—2023年采用分层整群抽样方法,对通州区11所学校的1485个学生家庭进行问卷调查。采用单因素分析比较不同人口学背景下家庭食物环境健康水平差异,相关因素分析采用二元多因素Logistic回归模型。结果通州区中小学生家庭食物环境健康水平得分(四分位间距)中位数为64.32(12.28)分,总达标率(≥60分)为67.41%;家庭喂养模式的健康水平得分[58.33(11.11)分]及达标率(42.76%)在家庭食物环境的5个维度中排名最后。乡镇家庭(OR=1.78,95%CI=1.41~2.25)、初中(OR=1.42,95%CI=1.07~1.87)和高中(OR=2.28,95%CI=1.73~3.00)学生家庭、单亲家庭(OR=1.89,95%CI=1.15~3.10)以及家长肥胖体型(OR=1.81,95%CI=1.23~2.65)的学生家庭食物环境健康水平未达标的风险更高(P值均<0.05)。结论通州区中小学生家庭食物环境总体健康水平不容乐观,家庭喂养模式健康水平亟待改善。应采取针对性措施以有效提升家庭食物环境健康水平,促进儿童青少年的健康成长。

关键词：家庭膳食环境回归分析学生