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Numerical simulation of aircraft arresting process with an efficient full-scale rigid-flexible coupling dynamic model

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Chinese Journal of Aeronautics 2024年第5期37卷 586-602页

作者： haoyuan SHAO Daochun li Zi KAN Lanxi BI Zhuoer YAO Jinwu XIANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Tianmushan Laboratory Hangzhou 310023China

The arresting process of carrier-based aircraft is widely recognized as a challenging task,characterized by the highest accident rate among all carrier-based aircraft operations.Dynamic simulation plays a crucial role in assessing the intricate responses of the arresting process,favoring the design of carrier-based aircraft.An efficient and accurate rigid-flexible coupling model for analyzing the dynamic response of the arresting process is proposed.By combining the dynamic characteristics of airframe,landing gear,arresting hook and arresting gear system,the rigid-flexible coupling dynamic model is established to reflect the relative motion of the coupling parts and arresting load.The dynamic model is verified through simulations of landing gear landing drops and by comparing the arresting simulation results with corresponding data in the US military standard.Additionally,simulations of the arresting process under different off-center distance and aircraft yaw angle are conducted to obtain the dynamic response of the aircraft during the arresting process.The result indicates that the rigid-flexible coupling dynamic model proposed is effective for analyzing the arresting dynamics response of carrier-based aircraft.The axial force of the arresting cable on both sides of the hook engagement point,pitch and yaw angle of aircraft are inconsistent under yaw and off-center arresting.The analysis method and obtained results provide valuable references for assessing the dynamic responses of carrier-based aircraft during arresting process and offer valuable in-sights in the design of carrier-based aircraft.

关键词： Carrier-based aircraft Deck landing Rigid-flexible coupling dynamic model Finite element method Dynamic analysis

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A green cross-linking method for the preparation of renewable threedimensional graphene sponges for efficient adsorption of Congo red dye

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Chinese Journal of Chemical Engineering 2024年第2期66卷 84-93页

作者： Zhuang liu Bo Gao haoyuan Han Yuling li Haiyang Fu Donghui Wei Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China

Graphene-based materials possess significant potential for the treatment of dye wastewater due to their exceptional adsorption properties toward stubborn pollutants.However,their utilization is hindered by high preparation costs,low yields,environmental pollution during synthesis,and challenges in regenerating the adsorbent.This study proposes a novel approach to address these limitations by developing nitrogen-doped three-dimensional(3D)polyvinyl alcohol(PVA)crosslinked graphene sponges(N-PGA)using a cross-linking method with ammonium carbonate.This method offers a relatively mild,environmentally friendly approach.Ammonium carbonate serves as both a reducing and modifying agent,facilitating the formation of the intrinsic structure of N-PGA and acting as a nitrogen source.Meanwhile,PVA is utilized as the cross-linking agent.The results demonstrate that N-PGA exhibits a favorable internal 3D hierarchical porous structure and possesses robust mechanical properties.The measured specific surface area(BET)of N-PGA was as high as406.538 m^(2)·g^(-1),which was favorable for its efficient adsorption of Congo red(CR)dye molecules.At an initial concentration of 50 mg·L^(-1),N-PGA achieved an impressive removal rate of 89.6%and an adsorption capacity of 112 mg·g^(-1)for CR dye.Furthermore,it retained 79%of its initial adsorption capacity after 10 cycles,demonstrating excellent regeneration performance.In summary,the synthesized N-PGA displays remarkable efficacy in the adsorption of CR dye in wastewater,opening up new possibilities for utilizing 3D porous graphene nanomaterials as efficient adsorbents in wastewater treatment.

关键词： Green chemistry Graphene sponge Adsorbents Adsorption Congo red Regeneration

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Quantification of the concrete freeze–thaw environment across the Qinghai–Tibet Plateau based on machine learning algorithms

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Journal of Mountain Science 2024年第1期21卷 322-334页

作者： QIN Yanhui MA haoyuan ZHANG Lele YIN Jinshuai ZHENG Xionghui li Shuo Department of Civil Engineering Qingdao University of TechnologyQingdao 266520China Department of Geography Qinghai Normal UniversityXining 810008China

The reasonable quantification of the concrete freezing environment on the Qinghai–Tibet Plateau(QTP) is the primary issue in frost resistant concrete design, which is one of the challenges that the QTP engineering managers should take into account. In this paper, we propose a more realistic method to calculate the number of concrete freeze–thaw cycles(NFTCs) on the QTP. The calculated results show that the NFTCs increase as the altitude of the meteorological station increases with the average NFTCs being 208.7. Four machine learning methods, i.e., the random forest(RF) model, generalized boosting method(GBM), generalized linear model(GLM), and generalized additive model(GAM), are used to fit the NFTCs. The root mean square error(RMSE) values of the RF, GBM, GLM, and GAM are 32.3, 4.3, 247.9, and 161.3, respectively. The R^(2) values of the RF, GBM, GLM, and GAM are 0.93, 0.99, 0.48, and 0.66, respectively. The GBM method performs the best compared to the other three methods, which was shown by the results of RMSE and R^(2) values. The quantitative results from the GBM method indicate that the lowest, medium, and highest NFTC values are distributed in the northern, central, and southern parts of the QTP, respectively. The annual NFTCs in the QTP region are mainly concentrated at 160 and above, and the average NFTCs is 200 across the QTP. Our results can provide scientific guidance and a theoretical basis for the freezing resistance design of concrete in various projects on the QTP.

关键词： Freeze–thaw cycles Quantification Machine learning algorithms Qinghai–Tibet Plateau Concrete

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Fabrication of amorphous FeCoNiCuMnP x high-entropy phosphide/carbon composites with a heterostructured fusiform morphology for efficient oxygen evolution reaction

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Journal of Materials Science & Technology 2024年第1期168卷 62-70页

作者： Yifan Zhou Longqing Gao haoyuan Chen Hao Wang Juan Zhang Xiumin li Fangfang Duo Guoqing Guan School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Graduate School of Sustainable Community Studies Hirosaki University1-BunkyochoHirosaki 036-8560Japan Graduate School of Science and Technology Hirosaki University3-BunkyochoHirosaki 036-8561Japan Xinxiang University School of Chemistry&Materials EngineeringXinxiang 453003China Energy Conversion Engineering Laboratory Institute of Regional InnovationHirosaki University3-BunkyochoHirosaki 036-8561Japan

Amorphous high-entropy materials with abundant defects,coordinatively unsaturated sites,and loosely bonded atoms could exhibit excellent electrocatalytic performance.However,how to fabricate such ma-terials with nanostructure as well as amorphous structure is still full of challenges.In this work,high-entropy metal organic framework(HE-MOF)is employed as the self-sacrificial template to fabricate FeCoNiCuMnP x high-entropy phosphide/carbon(HEP/C)composites.The obtained composite shows a het-erostructured fusiform morphology,in which the HEP is encapsulated by a carbon layer,revealing high electron conductivity as well as rich catalytic active sites for oxygen evolution reaction(OER).Beside,it is found that there is a short-range ordered crystal structure in the amorphous phase,which is bene-ficial for revealing high OER catalytic activity as well as good stability.As a result,the optimum HEP/C composite shows an overpotential 239 mV@10 mA cm^(−2)with a small Tafel slope of 72.5 mV dec^(−1) for catalyzing OER in alkaline solution.

关键词： Water electrolysis Oxygen evolution reaction High-entropy MOFs High-entropy phosphides Amorphous structure

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Research on Electromagnetic Wave Absorption Based on Electrospinning Technology

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Chinese Journal of Chemistry 2024年第7期42卷 777-789页

作者： Baoding li Jing Qiao Yue liu haoyuan Tian Wei liu Qilei Wu Zhou Wang Jiurong liu Zhihui Zeng Key Laboratoryfor liquid-Solid StructuralEvolution and Processing of Materials Schoolof Materials Science and EngineeringShandong UniversityJinanShandong 250061China China North Industries Group 53rd Research Institute JinanShandong 250000China School of Mechanical Engineering Shandong UniversityJinanShandong 250061China Institute of Crystal Materials State Key Laboratory of Crystal MaterialsShandong UniversityJinanShandong 250100China Shenzhen Research Institute of Shandong University ShenzhenGuangdong 518057China Science and Technology on Electromagnetic Compatibility Laboratory China Ship Development and Design CentreWuhanHubei 430064China suzhou Research Institute of Shandong University SuzhouJiangsu215123China

At present,in order to overcome electromagnetic interference and prevent electromagnetic harm,the research of new and efficient electromagnetic wave absorbing materials has become the research focus in the field of materials science.The one-dimensional structure can promote the impedance matching and attenuation characteristics of the absorbing materials.Electrospinning,as an effective method to prepare nanofibers with high length-diameter ratio,has been widely concerned because it is suitable for struc-tural design of various materials.In this paper,the research progress and absorption properties of nano-fiber materials prepared by electrospinning combined with different processes are introduced.

关键词： Electromagnetic wave(EMW)absorbing Electrospinning Nanofiber Impedance matching Nanocomposite

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A Combined Countermeasure Against Side-Channel and Fault Attack with Threshold Implementation Technique

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Chinese Journal of Electronics 2023年第2期32卷 199-208页

作者： JIAO Zhipeng CHEN Hua FENG Jingyi KUANG Xiaoyun YANG Yiwei li haoyuan FAN limin Trusted Computing and Information Assurance Laboratory Institute of SoftwareChinese Academy of Sciences University of Chinese Academy of Sciences Electric Power Research Institute China Southern Power Grid

Side-channel attack(SCA) and fault attack(FA) are two classical physical attacks against cryptographic implementation. In order to resist them, we present a combined countermeasure scheme which can resist both SCA and FA. The scheme combines threshold implementation and duplication-based exchange techniques. The exchange technique can confuse the fault propagation path and randomize the faulty values. The threshold implementation technique can ensure a provable security against SCA. Moreover, it can also help to resist the FA by its incomplete property and random numbers. Compared with other methods, the proposed scheme has simple structure, which can be easily implemented in hardware and result in a low implementation cost. Finally, we present a detailed design for the block cipher light encryption device(LED) and implement it.The hardware cost evaluation shows our scheme has the minimum overhead factor.

关键词： Side-channel attack Fault attack Combined countermeasure Threshold implementation

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全域土地综合整治中文化空间再识别及其与三生空间的融合提升

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中国农业大学学报 2024年第3期29卷 189-203页

作者：梁浩源李晶中国矿业大学(北京)地球科学与测绘工程学院北京100083

为探究全域土地综合整治对文化空间与三生空间有机融合的促进作用,基于文献分析、比较研究及空间分析等方法,构建以文化空间识别为前提、以关系辨析为基础和以优化路径为措施的研究框架,并展开系统分析。结果表明:1)文化空间作为一种文... 详细信息

为探究全域土地综合整治对文化空间与三生空间有机融合的促进作用,基于文献分析、比较研究及空间分析等方法,构建以文化空间识别为前提、以关系辨析为基础和以优化路径为措施的研究框架,并展开系统分析。结果表明:1)文化空间作为一种文化资源传承的特殊空间,涵盖了承载历史人文古迹的社会空间范围以及包含山川水系界域的郊野空间范围。典型属性包括地域风土性(基本性属性)、活态传承性(根本性属性)及文化性(特殊性属性)。主要类型包括法定文化空间、潜在文化空间及文化联系空间等3种;2)全域土地综合整治与文化保护的演化历程可分为相互独立、整治优先于文化、整治与文化并行以及整治与文化融合的4个主要阶段。新时期全域土地综合整治实现了由单一要素治理转向全要素治理、由仅注重生产空间发展拓展为“一文三生”空间协调发展;3)实施综合整治过程中文化空间与三生空间要素之间可能面临的位置冲突类型主要涵盖7个一级类、38个二级类,并且不同整治对象中涵盖文化资源的类型差异较为显著;4)从要素、空间和整治3个维度构建了促进文化空间与三生空间融合提升的理论框架。具体地,结合微观(具体位置)、中观(主要关系)和宏观(政策管控)3个尺度,详细阐述了文化空间与三生空间融合提升的措施。综上,本研究可为新时期全域土地综合整治的深入研究提供新思路。

关键词：全域土地综合整治文化空间三生空间融合

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物理赋能的助航灯具清洗数字孪生构建

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北京航空航天大学学报 2024年第3期50卷 785-795页

作者：董慧芬孙浩远严力武云霞中国民航大学电子信息与自动化学院天津300300

机场助航灯具清洗设备工作时需要远程实时监测设备状态和清洗质量。数字孪生通过虚拟平台映射清洗设备的工作情况,而目前虚拟环境的建立仍大量依赖于数据驱动,自身缺乏感知进化和虚拟仿真的能力,且对被执行件的关注较少。针对以上问题,... 详细信息

机场助航灯具清洗设备工作时需要远程实时监测设备状态和清洗质量。数字孪生通过虚拟平台映射清洗设备的工作情况,而目前虚拟环境的建立仍大量依赖于数据驱动,自身缺乏感知进化和虚拟仿真的能力,且对被执行件的关注较少。针对以上问题,提出基于多物理引擎的数字孪生模型。该系统利用CoppeliaSim构建数据和脚本双驱动的虚拟空间,融合了虚拟传感和视觉检测,并通过BlueZero实现实时通信。为解决通信延迟造成的数据流阶梯跳跃的问题,提出一种基于改进均值滤波的运动同步性增强算法,内嵌在Qt建立的数据集成子系统中。实验结果表明:经运动增强后,所提系统的虚实同步误差为74 ms,满足同步性要求;清洗机械臂关节角度跟踪的均方误差为0.827°,末端空间位置跟踪误差不超过2.775 mm,满足跟踪精度要求;所提模型能够动态呈现灯具被清洗时的污斑状况,证明了所提模型的合理性,满足助航灯具清洗过程的应用需求。

关键词：数字孪生助航灯具机械臂粒子模型状态监测同步性增强

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基于遗传编程的符号回归在化学和材料研究中的应用与展望

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材料导报 2024年第S1期38卷 268-274页

作者：田嘉欣李浩源上海大学微电子学院上海201800

化学和材料学科的理论进步可以促进化学反应设计、材料合成和工艺条件优化。目前,在许多前沿领域的复杂问题中,传统自底向上的推导理论面临诸多挑战,而基于遗传编程的符号回归方法在挖掘数据关系方面展示了独特的优势,为解决复杂问题提... 详细信息

化学和材料学科的理论进步可以促进化学反应设计、材料合成和工艺条件优化。目前,在许多前沿领域的复杂问题中,传统自底向上的推导理论面临诸多挑战,而基于遗传编程的符号回归方法在挖掘数据关系方面展示了独特的优势,为解决复杂问题提供了新的思路。本文主要综述了基于遗传编程的符号回归方法的原理、优势及局限性,讨论了其近年来的发展趋势,整理了简单易用的遗传编程工具,进而阐述了该方法在化学与材料领域的代表性应用,最后对遗传编程在材料与化学领域的未来发展方向进行了展望。

关键词：可解释机器学习模型符号回归遗传编程性质预测工艺条件优化

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面向云存储的属性基双边访问控制方案

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通信学报 2024年第4期45卷 128-136页

作者：李琦樊昊源陈伟熊金波韩立东李瑞南京邮电大学计算机学院江苏南京210023 杭州师范大学浙江省密码技术重点实验室浙江杭州311121 南京邮电大学通达学院江苏扬州225127 福建师范大学计算机与网络空间安全学院福建福州350117 西安电子科技大学计算机科学与技术学院陕西西安710071

针对目前云存储中细粒度双边访问控制机制安全模型较弱且外包解密结果缺乏验证的问题,提出了一种面向云存储数据的属性基双边访问控制方案。首先,提出了自适应安全可验证外包双边CP-ABE的形式化定义和安全模型;其次,以此为基础并结合批... 详细信息

针对目前云存储中细粒度双边访问控制机制安全模型较弱且外包解密结果缺乏验证的问题,提出了一种面向云存储数据的属性基双边访问控制方案。首先,提出了自适应安全可验证外包双边CP-ABE的形式化定义和安全模型;其次,以此为基础并结合批量可验证技术在合数阶群上设计了双边访问控制方案,支持数据拥有者与数据使用者同时为对方定义访问策略;最后,安全性分析表明,所提方案在自适应安全模型下针对选择明文攻击与选择消息攻击是不可区分的和存在性不可伪造的。实验结果显示,所提方案减轻了用户端的匹配、解密以及验证阶段的计算开销。

关键词：云存储双边访问控制自适应安全批量可验证外包解密

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