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Chinese Journal of Aeronautics 2024年第2期37卷 482-500页

作者： Xiaohe wang Zengqiang CAO yuehaoxuan wang Yingjiang GUO School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China NPU Xuhang Electromagnetic Technology Co. Ltd.Xi’an 710100China

As the controlled research of Dynamic Installation(DI)and Static Installation(SI),a new interference installation method was developed based on electromagnetic loading to enhance the mechanical properties of composite *** different interference-fit sizes were considered,ranging from a net fit to 2.0%.The experiments were conducted to evaluate the installation resistance and the mechanical behavior of the joint under external ***,an FFA model to model the stress distribution and damage behavior of the bolt-hole contact interface was *** load-displacement curve and damage modes of experiments were used to verify the FEA *** results show that the installation resistance during DI process was remarkably lower than that of SI process corresponding to all interference-fit sizes,and the stress amplitudes induced by interference were larger and widely *** damage of the hole wall was positively correlated with interference fit size,but DI can significantly reduce the damage compared to *** performance tests,DI enhanced the static bearing capacity and extended longer fatigue life of the joints than *** methods can be an effective way to achieve highly reliable interference joints in composite structures.

关键词： Carbon Fiber-Reinforced Polymer(CFRP) Bolted joints Interference-fit Electromagnetic installation Finite Element Analysis(FEA) Damage mechanics Bearing behavior

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基于电磁加载的冲击测试方法及应用

航空制造技术 2024年第7期67卷 112-124页

作者：王晓荷曹增强郭映江郭程翔王玥浩轩西北工业大学西安710072 陕西大工旭航有限公司西安710072

针对国防军工和航空航天对材料、结构或产品进行冲击试验的广泛需求,以及现有冲击测试技术在加载速度、加载力、安全隐患及模式单一等方面存在的问题,提出了基于电磁加载的冲击测试方法,开发了电磁加载的冲击测试系统。电磁力驱动的冲... 详细信息

针对国防军工和航空航天对材料、结构或产品进行冲击试验的广泛需求,以及现有冲击测试技术在加载速度、加载力、安全隐患及模式单一等方面存在的问题,提出了基于电磁加载的冲击测试方法,开发了电磁加载的冲击测试系统。电磁力驱动的冲击测试方法可针对不同的试验对象和不同试验要求,通过调整电源控制参数(主要是电容值和充电电压值)实现加载脉宽、载荷幅值及加载速度的精确调整和控制;通过改变电磁加载头方向便可实现拉伸-压缩试验的快速转换。此外,针对结构受复杂冲击加载的动态测试需求,基于电磁驱动的多轴多向加载可通过控制程序精准控制多驱动头同时放电,从而实现多轴多向同步加载,保证了作用于试件材料上的各向冲击载荷的同步性。因此,基于电磁加载的测试技术具有可控性好、重复性高、测试精度和试验效率高等优势,基于电磁加载的冲击测试解决了传统测试方法加载速度范围小、测试应变率范围有限、大加载力冲击测试难等难题,实现了冲击测试试验安全、稳定、可靠及更加精确的控制和测量。

关键词：电磁加载动态冲击电磁霍普金森杆低速冲击应变率

基于电磁铆枪的CFRP结构干涉螺栓动态压入方法研究

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航空制造技术 2023年第23期66卷 52-59页

作者：王晓荷郭映江王玥浩轩李亮西北工业大学西安710072

为提高复合材料螺栓结构的干涉配合连接质量和力学性能,提出了基于电磁铆枪的CFRP干涉配合螺栓动态压入(Dynamic press-in,DI)方法。对DI方法的压入工艺进行了试验研究,并与静态压入(Static press-in,SI)方法的压入质量进行了对比。测... 详细信息

为提高复合材料螺栓结构的干涉配合连接质量和力学性能,提出了基于电磁铆枪的CFRP干涉配合螺栓动态压入(Dynamic press-in,DI)方法。对DI方法的压入工艺进行了试验研究,并与静态压入(Static press-in,SI)方法的压入质量进行了对比。测量得出了干涉配合螺栓压入过程的压入力–位移曲线,从宏观和微观两方面评估了压入方法和干涉量对层压板压入损伤的影响。此外,对不同压入方法接头力学性能进行了对比,评估了DI对接头性能的连接效果,并初步探讨了DI方法有益于接头性能提高的机理。结果表明,与SI相比,DI能显著降低干涉配合压入阻力,且随着干涉量的增大这一优势更加明显。压入损伤对比结果显示,DI方法有助于钉孔装配界面质量的提高。在静拉伸试验中,DI方法试样比SI方法试样表现出更高的极限承载强度和连接刚度。

关键词：碳纤维增强树脂基复合材料(CFRP) 螺栓结构干涉配合装配界面行为承载性能

The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： Qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory

Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： wang Yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

Light People: Professor Fanglin Bao and his cover story

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Light(Science & Applications) 2024年第6期13卷 1015-1020页

作者： Ji wang School of Science Westlake UniversityHangzhouZhejiangPR China

Qu Yuan,a renowned ancient Chinese poet,once pondered in his work Heavenly Inquiry:“If the sun’s light is absent,from where does the radiance of the Hero Flower emanate?”The ability to see clearly in the darkest of nights has long been a sought-after magical power by *** holds not only immense technological significance for computer vision and remote sensing but also profound implications for transcending the dichotomy between day and night in our daily *** Fanglin Bao from Westlake University has made significant breakthroughs in this field,bringing us closer to a world where we can transform night into *** groundbreaking research on Heat-Assisted Detection and Ranging(HADAR)and night vision was featured as the cover story in Nature on July 26,2023.

关键词： bringing breakthrough holds

A multi-source information fusion layer counting method for penetration fuze based on TCN-LSTM

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Defence Technology（防务技术） 2024年第3期33卷 463-474页

作者： Yili wang Changsheng Li Xiaofeng wang Nanjing University of Science and Technology Nanjing 210094JiangsuChina State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ferromagnetic materials,thereby posing challenges in accurately determining the number of *** address this issue,this research proposes a layer counting method for penetration fuze that incorporates multi-source information fusion,utilizing both the temporal convolutional network(TCN)and the long short-term memory(LSTM)recurrent *** leveraging the strengths of these two network structures,the method extracts temporal and high-dimensional features from the multi-source physical field during the penetration process,establishing a relationship between the multi-source physical field and the distance between the fuze and the target plate.A simulation model is developed to simulate the overload and magnetic field of a projectile penetrating multiple layers of target plates,capturing the multi-source physical field signals and their patterns during the penetration *** analysis reveals that the proposed multi-source fusion layer counting method reduces errors by 60% and 50% compared to single overload layer counting and single magnetic anomaly signal layer counting,*** model's predictive performance is evaluated under various operating conditions,including different ratios of added noise to random sample positions,penetration speeds,and spacing between target *** maximum errors in fuze penetration time predicted by the three modes are 0.08 ms,0.12 ms,and 0.16 ms,respectively,confirming the robustness of the proposed ***,the model's predictions indicate that the fitting degree for large interlayer spacings is superior to that for small interlayer spacings due to the influence of stress waves.

关键词： Penetration fuze Temporal convolutional network(TCN) Long short-term memory(LSTM) Layer counting Multi-source fusion

Assessment of tree-ring mercury radial translocation and age effect in Masson pine:Implications for historical atmospheric mercury reconstruction

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Journal of Environmental Sciences 2024年第4期138卷 266-276页

作者： Xu Liu Xun wang Dingyong wang College of Resources and Environment Southwest UniversityChongqing 400715China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the *** this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at *** in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric *** showed that distinct variabilities among Masson pine tree-ring Hg concentration *** Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric *** found a distinct age effect that the tree ring of young trees had the higher Hg ***,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree *** modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in *** finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.

关键词： Masson pine Tree-ring mercury Radial translocation Tree age effect

Framework for Preventive Control of Power Systems to Defend Against Extreme Events

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 856-870页

作者： Yuwei Xiang Tong wang Zengping wang State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

Enhancing power system resilience against extreme events is becoming increasingly critical. This paper discusses a unified framework for preventive control of power systems to enhance system resilience, which includes three parts: resilience assessment, resilience grading, and resilience enhancement. First, the resilience assessment contains facility-level and system-level resilience assessment. The concept of fragility curve is used in the facility-level resilience assessment. Various resilience indices are developed in system-level resilience assessment to roundly depict the impacts of extreme events on power systems and determine the system resilience. On this basis, the resilience is divided into different levels by resilience grading strategy, which can efficiently quantify the severity of the impact of extreme events and provide decision-making for the resilience enhancement strategies. Then, control strategies for enhancing power system resilience are also divided according to different resilience levels. A controlled islanding based preventive control is proposed to enhance system resilience, which aims to strengthen the first defensive line of power systems to deal with extreme events. Finally, taking the typhoon disaster in extreme events as an example, two tests carried out with two typhoons demonstrate the efficiency of the proposed method.

关键词： Controlled islanding extreme events power system resilience preventive control