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Journal of Systems Science & Complexity 2024年第1期37卷 169-183页

作者： CHENG Daizhan meng Min zhang Xiao JI Zhengping Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China department of Control Science and engineering School of Electronics and Information EngineeringTongji UniversityShanghai 201210China National Center for Mathematics and Interdisciplinary Sciences Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100149China.

The semi-tensor product(STP)of matrices is generalized to multidimensional arrays,called the compound product of *** product is first defined for three-dimensional hypermatrices with compatible orders and then extended to general *** different types of hyperdeterminants are introduced and certain properties are *** Lie groups and Lie algebras corresponding to the hypermatrix products are ***,these results are applied to dynamical systems.

关键词： Compound semi-tensor product hyperdeterminants hypereigenvalues and hypereigenvectors hypergeneral linear groups hypermatrices.

A novel three-inflection-point sliding mode control framework for forward-tilting morphing aerospace vehicle with performance constraints and actuator faults

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Chinese Journal of Aeronautics 2024年第8期37卷 293-310页

作者： Xinkai LI Lei DOU Hongli zhang Yue meng School of electrical engineering Xinjiang UniversityUrumqi 830047China

A prescribed performance control scheme based on the three-inflection-point hyperbolic function and predefined time performance function is proposed to solve the trajectory tracking problem of the forward-tilting morphing aerospace vehicle with time-varying actuator *** accurately estimate the loss degree of actuator faults,an immersion and invariance observer based on the predefined time dynamic scale factor is designed to estimate and compensate it.A composite dynamic sliding mode surface is designed using a three-inflection-point hyperbolic function,and a novel three-inflection-point sliding mode control framework is *** convergent domain of the sliding manifold is adjusted by parameters,and the system error convergence is controllable.A transfer function is designed to eliminate the sensitivity of the three-inflection-point hyperbolic sliding mode to the unknown initial state,and combined with the barrier Lyapunov function,and the performance constraint of the system is *** global asymptotic stability of the system is demonstrated using a strict mathematical *** effectiveness and superiority of the proposed control scheme are proven by simulation experiments.

关键词： Morphing aerospace vehicle Actuator faults Immersion and invariance Three-inflection-point sliding mode control Prescribed performance control

Ultra-thin robust CNT@GC film integrating effective electromagnetic shielding and flexible Joule heating

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Nano Research 2024年第5期17卷 3462-3471页

作者： Ding zhang Chunhui Wang meng Li Weixue meng Shipeng zhang mengdan Yang Xinguang Huang Yingjiu zhang Yuanyuan Shang Anyuan Cao Key Laboratory of Materials Physics(Ministry of Education) School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou450052China Electron Microscopy Center Yunnan UniversityKunming650091China School of Materials Science and engineering Peking UniversityBeijing100871China

The demand for lightweight,thin electromagnetic interference(EMI)shielding film materials with high shielding effectiveness(SE),excellent mechanical properties,and stability in complex environments is particularly pronounced in the realm of flexible and portable electronic ***,we developed an ultra-thin film(CNT@GC)in which the glassy carbon(GC)layer wrapped around and welded carbon nanotubes(CNTs)to form a core-shell network structure,leading to exceptional tensile strength(327.2 MPa)and electrical conductivity(2.87×10^(5) S·m^(−1)).The CNT@GC film achieved EMI SE of 60 dB at a thickness of 2µm after post-acid treatment and high specific SE of 3.49×10^(5) dB·cm^(2)·g^(−1),with comprehensive properties surpassing those of the majority of previous shielding ***,the CNT@GC film exhibited Joule heating capability,reaching a surface temperature of 135℃at 3 V with a fast thermal response of about 0.5 s,enabling anti-icing/de-icing *** work presented a methodology for constructing a robust CNT@GC film with high EMI shielding performance and exceptional Joule heating capability,demonstrating immense potential in wearable devices,defense,and aerospace applications.

关键词： core-shell structure ultra-thin lightweight film robust film electromagnetic shielding Joule heating

Failure characteristics and fracture mechanism of overburden rock induced by mining:A case study in China

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International Journal of Coal Science & Technology 2024年第3期11卷 241-255页

作者： Jiawei Li meng zhang Changxiang Wang Changlong Liao Baoliang zhang department of Energy and Power engineering College of Mechanical and Transportation EngineeringChina University of Petroleum(Beijing)BeijingChina department of Energy and Power engineering Tsinghua UniversityBeijingChina College of Safety Science and engineering Anhui University of Science and TechnologyHuainan232000China School of Architecture and Civil engineering Liaocheng UniversityLiaocheng252000China

This study employs similar simulation testing and discrete element simulation coupling to analyze the failure and deformation processes of a model coal seam's *** caving area of the overburden rock is divided into three zones:the delamination fracture zone,broken fracture zone,and compaction *** caving and fracture zones'heights are approximately 110 m above the coal seam,with a maximum subsidence of 11 *** delamination fracture zone's porosity range is between 0.2 and 0.3,while the remainder of the roof predominantly exhibits a porosity of less than *** addition,the numerical model's stress analysis revealed that the overburden rock's displacement zone forms an'arch-beam'structure starting from 160 m,with the maximum and minimum stress values decreasing as the distance of advancement *** the stress beam interval of the overburden rock,the maximum value changes periodically as the advancement distance *** on a comparative analysis between observable data from on-site work and numerical simulation results,the stress data from the numerical simulation are essentially consistent with the actual results detected on-site,indicating the validity of the numerical simulation results.

关键词： Fracture development characteristics Similar simulation experiment Layer porosity Discrete element numerical simulation

A stable implicit nodal integration-based particle finite element method(N-PFEM)for modelling saturated soil dynamics

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Journal of Rock Mechanics and Geotechnical engineering 2024年第6期16卷 2172-2183页

作者： Liang Wang Xue zhang Jingjing meng Qinghua Lei department of Earth Sciences ETH ZürichZürich8092Switzerland department of Civil engineering and Industrial Design University of LiverpoolLiverpoolL693BXUK department of Civil Environmental and Natural Resources EngineeringLuleåUniversity of TechnologyLuleå97187Sweden department of Earth Sciences Uppsala UniversityUppsala75105Sweden

In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated *** approach incorporates the nodal integration technique into a generalised Hellinger-Reissner(HR)variational principle,creating an implicit PFEM *** mitigate the volumetric locking issue in low-order elements,we employ a node-based strain smoothing *** discretising field variables at the centre of smoothing cells,we achieve nodal integration over cells,eliminating the need for sophisticated mapping operations after re-meshing in the *** express the discretised governing equations as a min-max optimisation problem,which is further reformulated as a standard second-order cone programming(SOCP)***,pore water pressure,and displacements are simultaneously determined using the advanced primal-dual interior point ***,our numerical model offers improved accuracy for stresses and pore water pressure compared to the displacement-based PFEM *** experiments demonstrate that the N-PFEM efficiently captures both transient and long-term hydro-mechanical behaviour of saturated soils with high accuracy,obviating the need for stabilisation or regularisation techniques commonly employed in other nodal integration-based PFEM *** work holds significant implications for the development of robust and accurate numerical tools for studying saturated soil dynamics.

关键词： Particle finite element method Nodal integration Dynamic saturated media Second-order cone programming(SOCP)

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锅炉排烟温度高的原因及对应措施

科技创新与生产力 2011年第8期 93-94页

作者：张亚萌陕西能源职业技术学院机电工程系陕西咸阳712000

对锅炉排烟温度升高的原因进行了分析,并提出了相应的有效措施,对于降低排烟温度,提高锅炉效率具有一定的参考价值。

关键词：锅炉排烟温度热损失

Imitation Learning Based Real-time Decision-making of Microgrid Economic Dispatch Under Multiple Uncertainties

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1183-1193页

作者： Wei Dong Fan zhang meng Li Xiaolun Fang Qiang Yang School of Automation Hangzhou Dianzi UniversityHangzhou 310018China College of electrical engineering Zhejiang UniversityHangzhou 310027China

The intermittency of renewable energy generation,variability of load demand,and stochasticity of market price bring about direct challenges to optimal energy management of *** cope with these different forms of operation un-certainties,an imitation learning based real-time decision-mak-ing solution for microgrid economic dispatch is *** this solution,the optimal dispatch trajectories obtained by solv-ing the optimal problem using historical deterministic operation patterns are demonstrated as the expert samples for imitation *** improve the generalization performance of imita-tion learning and the expressive ability of uncertain variables,a hybrid model combining the unsupervised and supervised learn-ing is *** denoising autoencoder based unsupervised learning model is adopted to enhance the feature extraction of operation ***,the long short-term memory network based supervised learning model is used to efficiently characterize the mapping between the input space composed of the extracted operation patterns and system state variables and the output space composed of the optimal dispatch *** numerical simulation results demonstrate that under vari-ous operation uncertainties,the operation cost achieved by the proposed solution is close to the minimum theoretical *** with the traditional model predictive control method and basic clone imitation learning method,the operation cost of the proposed solution is reduced by 6.3%and 2.8%,respective-ly,overa test period of three months.

关键词： Energy management imitation learning datadriven decision economic dispatch

Composite Braking Control Strategy for Electromechanical-Hydraulic Vehicles

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1722-1732页

作者： Zewen meng Jichao Hong Hongxin zhang Tiezhu zhang Xiaoming Xu Qinghai Zhao Jian Yang College of Mechanical and electrical engineering Qingdao UniversityQingdao 260071China Power Integration and Energy Storage Systems engineering Technology Center(Qingdao) Qingdao 260071China School of Mechanical engineering University of Science and Technology BeijingBeijing 100083China Shunde Graduate School of University of Science and Technology Beijing Foshan 528000China

Short driving ranges and low braking energy recovery efficiencies are two recognized technical bottlenecks to be overcome in electric vehicles. In this paper, a novel electromechanical-hydraulic coupling system is proposed and integrated as a powertrain for electric vehicles, which can assist the electric vehicle to fully utilize its braking energy. The hydraulic regenerative braking force and electric regenerative braking force can provide all the braking needs using the medium and small braking intensities. Furthermore, an improved compound brake control strategy based on the braking force distribution is proposed and simulated. The results show that under the premise of ensuring braking stability, the electromechanical-hydraulic coupling driving electric vehicle can adapt to various working conditions with excellent energy-saving results. The hydraulic accumulator recovery efficiency is above 99%, and the state of charge consumption rate of the battery pack can be reduced by more than 9%. More importantly, the proposed hybrid power system can significantly improve the driving range and energy efficiency, as well as reduce the consumers' mileage anxiety in electric vehicles.

关键词： Braking control strategy electric vehicle electromechanical-hydraulic coupling energy recovery state of charge

Modeling human gastric cancers in immunocompetent mice

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Cancer Biology & Medicine 2024年第7期21卷 553-570页

作者： Weihong zhang Shilong Wang Hui zhang Yan meng Shi Jiao Liwei An Zhaocai Zhou department of Stomatology Department of Medical UltrasoundShanghai Tenth People's HospitalTongji University Cancer CenterTongji University School of MedicineShanghai 200072China State Key Laboratory of Genetic engineering School of Life SciencesZhongshan HospitalFudan UniversityShanghai 200032China Collaborative Innovation Center for Cancer Personalized Medicine School of Public HealthNanjing Medical UniversityNanjing 211166China

Gastric cancer(GC)is a major cause of cancer-related mortality *** is determined by multiple(epi)genetic and environmental factors;can occur at distinct anatomic positions of the stomach;and displays high heterogeneity,with different cellular origins and diverse histological and molecular *** heterogeneity has hindered efforts to fully understand the pathology of GC and develop efficient *** the past decade,great progress has been made in the study of GC,particularly in molecular subtyping,investigation of the immune microenvironment,and defining the evolutionary path and *** mouse models,particularly immunocompetent models that mimic the cellular and molecular features of human GC,in combination with organoid culture and clinical studies,have provided powerful tools for elucidating the molecular and cellular mechanisms underlying GC pathology and immune evasion,and the development of novel therapeutic ***,we first briefly introduce current progress and challenges in GC study and subsequently summarize immunocompetent GC mouse models,emphasizing the potential application of genetically engineered mouse models in antitumor immunity and immunotherapy studies.

关键词： Gastric cancer heterogeneity mouse model GEMM immunocompetent