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探矿工程 2001年第5期 58-61页

作者：李远宁段玉刚吴胜中国地质科学院探矿工艺研究所四川成都610081

论述了浅埋软弱地层隧道旋喷预衬砌支护的研究背景及国内外研究现状、室内试验、旋喷器具、施工工艺及应用情况 ,并与其它施工方法进行了对比。

关键词：隧道浅埋软弱地层水平旋喷预衬砌支护效果施工工艺有限元分析

Cerebral fat embolism following autologous fat injection in facial reconstruction:A case report

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World Journal of Clinical Cases 2025年第2期13卷 50-58页

作者： Xiu-Ying Chen Fa Shen Chang Cheng yu-Han Wang Wen-Chao Cheng De-Zhi yuan Wen Huang Department of Neurology Chongqing Emergency Medical CenterChongqing University Central HospitalChongqing 400000China Department of Neurology Xinqiao HospitalThe Army Medical University(Third Military Medical University)Chongqing 400000China

BACKGROUND Autologous fat injection in facial reconstruction is a common cosmetic *** cerebral fat embolism(CFE)as a complication is rare,it carries serious health *** SUMMARY We present a case of a 29-year-old female patient who developed acute CFE following facial fat filling *** the surgery,the patient experienced symptoms including headache,nausea,vomiting,and difficulty breathing,which was followed by neurological symptoms such as slurred speech and left-sided *** physical examination and auxiliary investigations,including blood tests,head and neck computed tomography angiography,and cranial magnetic resonance diffusion-weighted imaging,were performed upon *** clinical diagnosis was acute cerebral embolism following facial fat filling *** included measures to improve cerebral circulation,dehydration for intracranial pressure reduction,nutritional support,and rehabilitation therapy for left limb *** patient showed a significant improvement in symptoms after 2 weeks of *** recovered left limb muscle strength to grade 5,had clear speech,and experienced complete relief of *** Our case highlights the potential occurrence of severe complications in patients undergoing fat injection in facial *** prevent these complications,plastic surgeons should enhance their professional knowledge and skills.

关键词： Cerebral fat embolism Mechanical thrombectomy Thrombolysis Steroid therapy Symptomatic treatment Case report

Petroleum hydrocarbons and their effects on fishery species in the Bohai Sea, North China

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Journal of Environmental Sciences 2011年第4期23卷 553-559页

作者： Sisi Xu Jinming Song Huamao yuan Xuegang Li Ning Li Liqin duan yu yu Key Laboratory of Marine Ecology and Environmental Sciences Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Systematic studies on the changes in concentrations of petroleum hydrocarbons （PHs） and their effects on fishery species in the Bohai Sea during 1974–2004 are presented. Changes in PHs concentrations were closely related to Yellow River runoff. Concentrations of PHs accumulated in fish and shrimp increased by about 0.712 mg/kg dry weight when trophic level of fish and shrimps increased by 1. Attention should also be paid to the high PHs concentrations in mollusks along the coastal waters of the Bohai Sea. Average concentration of PHs in the adjacent coastal waters of Tianjin City during 1996–2005 decreased the population growth rates of fish, crustaceans and mollusks in the Bohai Sea by 2.58%, 6.59% and 2.33%, respectively. Therefore, PHs have significantly contributed to the decline in fisheries in the Bohai Sea, and they must be reduced to realize the sustainable fisheries.

关键词： petroleum hydrocarbons fishery resources population growth rate toxicity Bohai Sea

Extremum seeking control for UAV close formation flight via improved pigeon-inspired optimization

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Science China(Technological Sciences) 2024年第2期67卷 435-448页

作者： yuan GuangSong duan HaiBin State Key Laboratory of Virtual Reality Technology and Systems School of Automation Science and Electrical EngineeringBeihang University(BUAA)Beijing 100083China

This paper proposes a comprehensive design scheme for the extremum seeking control(ESC)of the unmanned aerial vehicle(UAV)close formation *** proposed design scheme combines a Newton-Raphson method with an extended Kalman filter(EKF)to dynamically estimate the optimal position of the following UAV relative to the leading *** reflect the wake vortex effects reliably,the drag coefficient induced by the wake vortex is considered as a performance ***,the performance function is parameterized by the first-order and second-order terms of its Taylor series *** the excellent performance of nonlinear estimation,the EKF is used to estimate the gradient and the Hessian matrix of the parameterized performance *** output feedback of the proposed scheme is determined by iterative calculation of the Newton-Raphson *** with the traditional ESC and the classic ESC,the proposed design scheme avoids the slow continuous time integration of the *** allows a faster convergence of relative position ***,the proposed method can provide a smoother command during the seeking process as the second-order term of the performance function is taken into *** convergence analysis of the proposed design scheme is accomplished by showing that the output feedback is a supermartingale *** improve estimation performance of the EKF,a improved pigeon-inspired optimization(IPIO)is proposed to automatically tune the noise covariance *** Carlo simulations for a three-UAV close formation show that the proposed design scheme is robust to the initial position of the following UAV.

关键词： unmanned aerial vehicle close formation extremum seeking control Newton-Raphson method improved pigeon-inspired optimization

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ON THE CONVERGENCE OF THE NONNESTED V-CYCLE MULTIGRID METHOD FOR NONSYMMETRIC AND INDEFINITE SECOND-ORDER ELLIPTIC PROBLEMS

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Journal of Computational Mathematics 2006年第2期24卷 157-168页

作者： Huo-yuan duan Qun Lin LSEC ICMSEC Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China

This paper provides a proof for the uniform convergence rate （independently of the number of mesh levels） for the nonnested V-cycle multigrid method for nonsymmetric and indefinite second-order elliptic problems.

关键词： Nonnested V-cycle multigrid method Second-order elliptic problems.

Prescribed Performance Evolution Control for Quadrotor Autonomous Shipboard Landing

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1151-1162页

作者： Yang yuan Haibin duan Zhigang Zeng State Key Laboratory of Virtual Reality Technology and Systems the School of Automation Science and Electrical EngineeringBeihang UniversityBeijing 100083China State Key Laboratory of Virtual Reality Technology and Systems the School of Automation Science and Electrical EngineeringBeihang UniversityBeijing 100083 Virtual Reality Fundamental Research Laboratory Department of Mathematics and TheoriesPeng Cheng LaboratoryShenzhen 518000China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China

The shipboard landing problem for a quadrotor is addressed in this paper,where the ship trajectory tracking control issue is transformed into a stabilization control issue by building a relative position *** guarantee both transient performance and steady-state landing error,a prescribed performance evolution control(PPEC)method is developed for the relative position *** addition,a novel compensation system is proposed to expand the performance boundaries when the input saturation occurs and the error exceeds the predefined *** the wind and wave on the relative position model,an adaptive sliding mode observer(ASMO)is designed for the disturbance with unknown upper *** on the dynamic surface control framework,a shipboard landing controller integrating PPEC and ASMO is established for the quadrotor,and the relative position control error is guaranteed to be uniformly ultimately *** results have verified the feasibility and effectiveness of the proposed shipboard landing control scheme.

关键词： error integrating stabilization

Seed Storability in Rice: Physiological Foundations, Molecular Mechanisms, and Applications in Breeding

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Rice science 2024年第4期31卷 401-416,I0023-I0024页

作者： ZHOU Tianshun yu Dong WU Liubing XU yusheng duan Meijuan yuan Dingyang Longping Branch College of BiologyHunan UniversityChangsha 410125China State Key Laboratory of Hybrid Rice Hunan Hybrid Rice Research CenterHunan Academy of Agricultural SciencesChangsha 410125China Hunan Provincial Key Laboratory of Rice Stress Biology College of AgronomyHunan Agricultural UniversityChangsha 410128China

Long-term storage of crop seeds is critical for the conservation of germplasm resources, ensuring food supply, and supporting sustainable production. Rice, as a major food staple, has a substantial stock for consumption and production worldwide. However, its food value and seed viability tend to decline during storage. Understanding the physiological responses and molecular mechanisms of aging tolerance forms the basis for enhancing seed storability in rice. This review outlines the latest progress in influential factors, evaluation methods, and identification indices of seed storability. It also discusses the physiological consequences, molecular mechanisms, and strategies for breeding aging-tolerant rice in detail. Finally, it highlights challenges in seed storability research that require future attention. This review offers a theoretical foundation and research direction for uncovering the mechanisms behind seed storability and breeding aging-tolerant rice.

关键词： rice seed storability physiological response molecular mechanism aging-tolerant breeding

Graphene-based vertical thin film transistors

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Science China(Information Sciences) 2020年第10期63卷 42-53页

作者： Liting LIU yuan LIU Xiangfeng duan Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education School of Physics and ElectronicsHunan University Department of Chemistry and Biochemistry University of California

Vertical field effect transistors(VFETs), where the channel material is sandwiched between source-drain electrodes and the channel length is simply determined by its body thickness, have attracted considerable interest for high performance electronics owning to their intrinsic short channel length. To enable the effective gate modulation and current switching behavior, the electrode of conventional VFET is largely based on perforated metals, in which the gate electrical field could penetrate through. Recently,with the emerge of graphene, a new type of graphene based VFETs has been developed. With finite density of states and the weak electrostatic screening effect, graphene exhibits a field-tunable work-function and partial electrostatic transparency, it can thus function as an "active" contact with tunable graphene-channel junction, enabling entirely new transistor functions or higher device performance not previously *** this review, we discuss the research progresses of graphene-based VFET, including the its basic device structure, carrier transport mechanism, device performance and novel properties demonstrated.

关键词： graphene electrode vertical transistors thin film transistors van der Waals heterostructures

Reliability-based selective maintenance for redundant systems with dependent performance characteristics of components

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Journal of Systems Engineering and Electronics 2023年第3期34卷 804-814页

作者： CAO Hui duan Fuhai duan yu’nan School of Mechanical Engineering Dalian University of TechnologyDalian 116024China

The reliability-based selective maintenance(RSM)decision problem of systems with components that have multiple dependent performance characteristics(PCs)reflecting degradation states is addressed in this paper.A vine-Copulabased reliability evaluation method is proposed to estimate the reliability of system components with multiple ***,the marginal degradation reliability of each PC is built by using the Wiener stochastic process based on the PC’s degradation *** joint degradation reliability of the component with multiple PCs is established by connecting the marginal reliability of PCs using *** addition,two RSM decision models are developed to ensure the system accomplishes the next *** genetic algorithm(GA)is used to solve the constraint optimization problem of the models.A numerical example illustrates the application of the proposed RSM method.

关键词： D-vine genetic algorithm(GA) reliability-based selective maintenance(RSM) redundant system Wiener stochastic process

Conversion-type cathode materials for high energy density solid-state lithium batteries

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Journal of Energy Chemistry 2025年第1期 409-425页

作者： yuhao Ma Shihong Qing Hongyu Liu Chuntao Ma yuan yu Chuang yu Liping Wang School of Materials and Energy University of Electronic Science and Technology of China Zhejiang Provincial Key Laboratory of Fiber Materials and Manufacturing Technology Zhejiang Sci-Tech University State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology

Solid-state lithium batteries （SSLBs） are regarded as an essential growth path in energy storage systems due to their excellent safety and high energy *** particular,SSLBs using conversion-type cathode materials have received widespread attention because of their high theoretical energy densities,low cost,and *** the great progress in research and development of SSLBs based on conversiontype cathodes,their practical applications still face challenges such as blocked ionic-electronic migration pathways,huge volume change,interfacial incompatibility,and expensive processing *** review focuses on the advantages and critical issues of coupling conversion-type cathodes with solid-state electrolytes （SSEs）,as well as state-of-the-art progress in various promising cathodes （e.g.,FeS2,CuS,FeF3,FeF2,and S） in ***,representative research on conversion-type solid-state full cells is discussed to offer enlightenment for their practical ***,the energy density exhibited by the S cathode stands out impressively,while sulfide SSEs and halide SSEs have demonstrated immense potential for coupling with conversion-type ***,perspectives on conversion-type cathodes are provided at the material,interface,composite electrode,and battery levels,with a view to accelerating the development of conversion-type cathodes for high-energy–density SSLBs.

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