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基于有限元分析的大理、丽江地区穿斗式木结构山架抗震性能

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地震研究 2025年第1期48卷 100-111页

作者：叶阳杨健强明小娜周洋王杰刘绍昌高扬云南省地震局云南昆明650224 中国地震局昆明地震预报研究所云南昆明650224 德宏州防震减灾局云南芒市678400

通过实地调查,分析了大理、丽江地区木结构榫卯结构的配置情况以及二者结构上的差异。为了研究二者的抗震性能与受力特性,通过有限元软件对两个地区的典型穿斗式木结构山架进行低周往复荷载模拟。结果表明:丽江地区穿斗式木结构山架抗... 详细信息

通过实地调查,分析了大理、丽江地区木结构榫卯结构的配置情况以及二者结构上的差异。为了研究二者的抗震性能与受力特性,通过有限元软件对两个地区的典型穿斗式木结构山架进行低周往复荷载模拟。结果表明:丽江地区穿斗式木结构山架抗震性能优于大理地区,两地木结构的薄弱点均在横向构件与纵向构件的榫卯节点处,榫卯节点的薄弱点位于榫头末端,二者的抗侧刚度均不高,易在水平荷载下倾斜。

关键词：穿斗式木结构抗震性能大理丽江有限元分析

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骨科学领域组织透明化技术的应用与展望

中国组织工程研究 2025年第15期29卷 3227-3234页

作者：高阳高原马炳江岳辉石永新牡丹江医学院黑龙江省牡丹江市157011 深圳大学附属华南医院广东省深圳市518111 深圳市光明区人民医院广东省深圳市518106

背景:骨组织作为高度矿化且结构复杂的结缔组织,在维持生物体形态和功能中扮演关键角色,传统的成像技术难以满足对其深入观察的需求。组织透明化技术的出现使得研究者能够更加清晰地观察到骨内的细微结构,如骨小梁、骨髓腔以及与骨组织... 详细信息

背景:骨组织作为高度矿化且结构复杂的结缔组织,在维持生物体形态和功能中扮演关键角色,传统的成像技术难以满足对其深入观察的需求。组织透明化技术的出现使得研究者能够更加清晰地观察到骨内的细微结构,如骨小梁、骨髓腔以及与骨组织相互作用的神经和血管网络,为骨科学的研究和临床应用开辟了新的视角。目的:旨在全面梳理组织透明化技术在骨科学领域的应用,并探讨其在骨组织结构与功能研究、疾病机制解析以及治疗策略创新中的潜力,同时对其创新点进行展望。方法:检索覆盖中国知网和PubMed数据库,英文检索词为“tissue clearing,tissue optical,bone”等,中文检索词为“组织透明化、骨、骨缺损”等,结合布尔逻辑以优化检索策略。纳入与组织透明化技术和骨科学研究直接相关的期刊论文和学位论文,排除关联性不强、重复或数据不完整的文献。最终纳入82篇文献进行分析,关注点包括透明化技术的效能、应用范围及对骨科学研究的贡献。结果与结论:①组织透明化技术在骨结构分析、骨代谢研究、骨肿瘤的病理学特征、骨折愈合过程、骨感染的机制研究以及骨移植和植入物材料的生物相容性评价等多个领域均展现出其独特的应用优势;②该技术的应用不仅加速了骨科学领域的基础研究进展,也为临床治疗提供了新的策略和方法,其在骨科学研究领域具有广阔的应用前景。

关键词：组织透明化技术骨科学三维成像骨组织生物医学成像

Green’s functions for infinite planes and half-planes consisting of quasicrystal bi-materials

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第10期11卷 835-840页

作者： yang gao College of Science China Agricultural University Beijing 100083 China Institute of Mechanics University of Kassel Kassel D-34125 Germany

This paper deals with the combination of point phonon and phason forces applied in the interior of infinite planes and half-planes of 1D quasicrystal bi-materials. Based on the general solution of quasicrystals, a series of displacement functions are adopted to obtain Green's functions for infinite planes and bi-material planes composed of two half-planes in the closed form, when the two half-planes are supposed to be ideally bonded or to be in smooth contact. Since the physical quantities can be readily calculated without the need of performing any transform operations, Green's functions are very convenient to be used in the study of point defects and inhomogeneities in the quasicrystal materials.

关键词： Green’s functions 1D quasicrystal Infinite planes Half-planes Bi-materials

Near-Earth asteroid flyby trajectories from the Sun-Earth L2 for Chang’e-2’s extended flight

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Acta Mechanica Sinica 2013年第1期29卷 123-131页

作者： yang gao State Key Laboratory of Astronautic Dynamics Engineering and Technology Center for Space Utilization Chinese Academy of Sciences

Driven by curiosity about possible flight options for the Chang＇e-2 spacecraft after it remains at the Sun-Earth L2 point, effective approaches were developed for designing preliminary fuel-optimal near-Earth asteroid flyby trajectories. The approaches include the use of modified unstable manifolds, grid search of the manifolds＇ parameters, and a two-impulse maneuver for orbital phase matching and z-axis bias change, and are demonstrated to be effective in asteroid target screening and trajectory optimization. Asteroid flybys are expected to be within a distance of 2 × 10^7 km from the Earth owing to the constrained Earth-spacecraft communication range. In this case, the spacecraft＇s orbital motion is significantly affected by the gravities of both the Sun and the Earth, and therefore, the concept of the ＂he- liocentric oscillating-Kepler orbit＂ is proposed, because the classical orbital elements of the flyby trajectories referenced in the heliocentric inertial frame oscillate significantly with respect to time. The analysis and results presented in this study show that, among the asteroids whose orbits are the most accurately predicted, ＂Toutatis＂, ＂2005 NZ6＂, or ＂2010 CL19＂ might be encountered by Chang＇e-2 in late 2012 or 2013 with total impulses less than 100 rn/s.

关键词： Chang'e-2 Asteroid flyby Sun-Earth L2 Modified unstable manifolds Oscillating-Kepler orbit

Earth-moon Trajectory Optimization Using Solar Electric Propulsion

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Chinese Journal of Aeronautics 2007年第5期20卷 452-463页

作者： gao yang Academy of Opto-Electronics Chinese Academy of Sciences Beijing 100080 China

The optimization of the Earth-moon trajectory using solar electric propulsion is presented. A feasible method is proposed to optimize the transfer trajectory starting from a low Earth circular orbit （500 km altitude） to a low lunar circular orbit （200 km altitude）. Due to the use of low-thrust solar electric propulsion, the entire transfer trajectory consists of hundreds or even thousands of orbital revolutions around the Earth and the moon. The Earth-orbit ascending （from low Earth orbit to high Earth orbit） and lunar descending （from high lunar orbit to low lunar orbit） trajectories in the presence of J2 perturbations and shadowing effect are computed by an analytic orbital averaging technique. A direct/indirect method is used to optimize the control steering for the trans-lunar trajectory segment, a segment from a high Earth orbit to a high lunar orbit, with a fixed thrust-coast-thrust engine sequence. For the trans-lunar trajectory segment, the equations of motion are expressed in the inertial coordinates about the Earth and the moon using a set of nonsingular equinoctial elements inclusive of the gravitational forces of the sun, the Earth, and the moon. By way of the analytic orbital averaging technique and the direct/indirect method, the Earth-moon transfer problem is converted to a parameter optimization problem, and the entire transfer trajectory is formulated and optimized in the form of a single nonlinear optimization problem with a small number of variables and constraints. Finally, an example of an Earth-moon transfer trajectory using solar electric propulsion is demonstrated.

关键词： trajectory optimization solar electric propulsion analytic orbital averaging technique direct/indirect method

Demand-side Response Strategy of Multi-microgrids Based on an Improved Co-evolution Algorithm

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CSEE Journal of Power and Energy Systems 2021年第5期7卷 903-910页

作者： yang gao Qian Ai Key Laboratory of Control of Power Transmission and Conversion Shanghai Jiao Tong UniversityShanghai 200240China

An effective modeling and optimization method,which takes into account source-load-storage coordination,and full-time collaborative optimization within and outside micro-grids,is *** the operational conditions of various resources and their interactions,an energy management model for microgrids is proposed aiming at maximization of renewable energy utilization and minimization of overall system *** model is suitable for both real-time pricing and time-of-use *** microgrids,demand response and economic energy storage dispatch are introduced to enhance selfcoordination and self-balancing ability among different *** on whether there is still an imbalance between supply and demand after coordination within a niicrogrid,trade between it and external microgrids are optimized in a orderly manner by considering different transaction prices and usage ***,three different schemes are designed,where the Lagrangian multiplier method as well as a co-evolution algorithm are used to solve and analyze different examples,verifying the reliability and validity of the method proposed in this paper.

关键词： Terms—Co-evolution demand-side response multi-microgrids source-load-storage coordination.

Binder-and conductive additive-free Ga2O3 nanowires as a self-healing anode for lithium storage

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Progress in Natural Science:Materials International 2023年第2期33卷 203-210页

作者： yang gao Bin Wang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology

High-capacity anode materials have stimulated much attention to developing high-performance lithium-ion batteries. However, high-capacity anode materials commonly suffer from the pulverization matter that greatly hinders their practical applications, especially in terms of the high proportion of active materials. In this work, a Ga2O3nanowire electrode is synthesized by thermal evaporation and immediately used as an anode without the aid of binders and conductive additives. The 3D interconnected architecture of the Ga2O3nanowire electrode shortens lithium diffusion lengths and expedites reaction kinetics. The Ga2O3nanowires exhibit high elasticity and a self-healing ability which is inherited from metallic Ga formed during the electrochemical transition process, thus circumventing the formidable pulverization issue to a certain extent. Benefiting from the unique structural, mechanical, and chemical attributes, the as-grown Ga2O3nanowire electrode gives a high initial lithiation capacity of 1462 m Ah g-1under a current density of 0.1 A g-1. It delivers good cyclic stability with a reversible capacity of 445 m Ah g-1after 200 cycles at 0.5 A g-1. Furthermore, the investigation of lithium storage behaviors indicates the high rate capability of Ga2O3nanowires. This paper contributes to understanding binderand conductive additive-free electrodes consisting of high-capacity active materials from various viewpoints.

关键词： Lithium-ion battery Gallium oxide Nanowires Binder-free Mechanical testing

Defense Against Software-Defined Network Topology Poisoning Attacks

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Tsinghua Science and Technology 2023年第1期28卷 39-46页

作者： yang gao Mingdi Xu Platform Research and Development Department Wuhan Institute of Digital EngineeringWuhan 430073China

Software-Defined Network(SDN)represents a new network *** conventional networks,SDNs separate control planes and data *** function of a data plane is enabled using switches,whereas that of a control plane is facilitated by a *** controller learns network topologies and makes traffic forwarding ***,some serious vulnerabilities are gradually exposed in the topology management services of current SDN controller *** vulnerabilities mainly exist in host tracking and link discovery *** can exploit these weak points to poison the network topology information in SDN *** this study,a novel solution is proposed to defend against topology poisoning *** analyzing the existing topology attack principles and threat models,this work constructs legal conditions for host migration to detect host hijacking *** checking of the Link Layer Discovery Protocol(LLDP)source and integrity is designed to defend against link fabrication attacks.A relay-type link fabrication attack detection method based on entropy is also *** show that the proposed solution can effectively detect existing topological attacks and provide complete and comprehensive topological security protection.

关键词： Software-Defined Network(SDN) topology discovery topology poisoning attacks

Improving meta-learning model via meta-contrastive loss

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Frontiers of Computer Science 2022年第5期16卷 107-113页

作者： Pinzhuo TIAN yang gao Department of Computer Science and Technology Nanjing UniversityJiangsu 210023China

Recently,addressing the few-shot learning issue with meta-learning framework achieves great *** we know,regularization is a powerful technique and widely used to improve machine learning ***,rare research focuses on designing appropriate meta-regularizations to further improve the generalization of meta-learning models in few-shot *** this paper,we propose a novel metacontrastive loss that can be regarded as a regularization to fill this *** motivation of our method depends on the thought that the limited data in few-shot learning is just a small part of data sampled from the whole data distribution,and could lead to various bias representations of the whole data because of the different sampling ***,the models trained by a few training data(support set)and test data(query set)might misalign in the model space,making the model learned on the support set can not generalize well on the query *** proposed meta-contrastive loss is designed to align the models of support and query sets to overcome this *** performance of the meta-learning model in few-shot learning can be *** experiments demonstrate that our method can improve the performance of different gradientbased meta-learning models in various learning problems,e.g.,few-shot regression and classification.

关键词： meta-learning few-shot learning metaregularization deep learning