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地基SAR影像加权干涉叠加法及其应用

测绘科学 2024年第5期49卷 55-63页

作者：唐敏轩龙四春周健赖咸根吴文豪祝传广权永华李小勇湖南科技大学地球科学与空间信息工程学院湖南湘潭411201 中国建筑第五工程局有限公司广东深圳518108 中建五局土木工程有限公司长沙410011

为减弱影像噪声及影像失相干性的影响,提出地基SAR影像加权干涉叠加法。根据影像特征,提出热信噪比(TSNR)、相干系数、相位稳定性对地基SAR影像分组,并利用标准差标准化算法(Z-Score)对各像元点指标值进行定量处理,得到顾及3种影响因子... 详细信息

为减弱影像噪声及影像失相干性的影响,提出地基SAR影像加权干涉叠加法。根据影像特征,提出热信噪比(TSNR)、相干系数、相位稳定性对地基SAR影像分组,并利用标准差标准化算法(Z-Score)对各像元点指标值进行定量处理,得到顾及3种影响因子后的影像综合权值矩阵,再进行加权叠加处理。以湘潭市建筑基坑240景影像及盾构下穿湘潭北站10758景影像为实验对象,对上述数据进行处理后并与测量机器人数据进行对比。结果表明,该算法在长时序地基SAR影像处理方面效果较显著,PS点数量增加了4102个,与测量机器人数据相对误差不超0.5 mm,且较均值叠加法在影像处理方面对干涉相位噪声更敏感,能有效减弱影像在时间维噪声,弱化失相干影像,获得形变信息的最优估计。

关键词：地基SAR 影像加权叠加热信噪比相干系数相位稳定性

An Improved MAC Protocol for Underwater Acoustic Networks

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An Improved MAC Protocol for Underwater Acoustic Networks

Flabellariopteris, a new aquatic fern leaf from the Late Triassic of western Liaoning, China

第25届中国控制与决策会议

作者： Wang Ping Fu Donghao Xing Jianchun Yang Qiliang Wang Ronghao wu wenhao The PLA University of Science and Technology Urumuqi Urban construction Archives

ISBN: (纸本)9781467355339

Considering the particularity of underwater acoustic channel and the performance of underwater acoustic sensor networks, this paper presents a MAC layer protocol based on CDMA with throughput adaptive regulation and energy-efficient （TAEE-CDMA） protocol. On the premise that the MAI problem was suppressed, the protocol firstly used Lagrange multiplier method to make the node run with minimum energy consumption, then adjusted the transmit power of node to change the throughput size according to the dynamic changes of the node cache queue, which can ensure the monitoring task of network be completed and make the network run with optimal performance. The analysis and simulation results showed that the protocol had advantages of energy-efficient, real-time and high reliability.

关键词： Underwater Acoustic Network Throughput Energy-efficient Adaptive Regulation MAC

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Chinese Science Bulletin 2014年第20期59卷 2410-2418页

作者： Chunlin Sun Tao Li Yuling Na wenhao wu Yunfeng Li Lixia Wang Lijun Zhang Key Laboratory for Evolution of Past Life and Environment in Northeast Asia Ministry of Education Research Center of Paleontology & Stratigraphy of Jilin University Bureau of Fossil Protection and Management of Liaoning

An aquatic fern leaf,Flabellariopteris mii Sun *** *** the Late Triassic of Western Liaoning,China,is described and proposed as the type species of the new morphortaxon of the *** fossil leaves are preserved as *** fertile and rhizomatic materials are *** leaves attached at a common point on the top of the petiole are composed of two leaflets joined basally in an opposite *** petiole is *** leaflet is fan-shaped or semi-circular,and commonly divided into four wedge-shaped *** margin of lobes is usually incised,incisions shallow or deep,with bluntly rounded or notched *** veins are conspicuously dichotomous,but anastomoses and marginal vein are *** unique morphological features,including twoparted thin leaflets,size,shape,veins and slender petiole,indicate that the present specimen represents an aquatic fern,which is the oldest fossil record and the first megafossil evidence assignable to Marsileaceae from the Triassic floras.

关键词：蕨类植物植物叶子晚三叠世水生中国辽西化石记录信息产业部

基于“卫气内伐”理论辨治手足综合征思路探析

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江苏中医药 2024年第9期56卷 35-38页

作者：宣锡丰黄彬彬吴文昊徐晓翌浙江中医药大学第三临床医学院浙江杭州310053 衢州市中医医院浙江衢州324002

手足综合征是抗肿瘤治疗的常见并发症之一,主要表现为手足皮肤麻木或疼痛,可伴有脱屑、皲裂、渗液、破溃等,症状反复,迁延难愈,严重影响患者的生活质量和治疗依从性。从“卫气内伐”理论分析,脏腑失调,营卫化源失常、循行受阻,致使卫气... 详细信息

手足综合征是抗肿瘤治疗的常见并发症之一,主要表现为手足皮肤麻木或疼痛,可伴有脱屑、皲裂、渗液、破溃等,症状反复,迁延难愈,严重影响患者的生活质量和治疗依从性。从“卫气内伐”理论分析,脏腑失调,营卫化源失常、循行受阻,致使卫气内伐而伏于脉中,在内不能温煦脏腑,在外不能固表御邪,加之在内的药毒(抗肿瘤药物)和在外之风寒湿邪袭扰,虚实夹杂,而成手足综合征。治当健脾和胃、温阳益肾、调和脏腑、祛邪蠲痹,方能营卫得源、清浊得分,卫气得温、脏腑得煦,血脉得通、卫行得畅,身无邪扰、内外皆安。附验案1则以佐证。

关键词：手足综合征卫气内伐脏腑失调调卫和营调和脏腑

Cu_(2)Se@C thin film with three-dimensional braided structure as a cathode material for enhanced Cu^(2+) storage

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Chinese Chemical Letters 2024年第5期35卷 523-528页

作者： wenhao Chen Muxuan wu Han Chen Lue Mo Yirong Zhu College of Materials and Advanced Manufacturing Hunan University of TechnologyZhuzhou 412007China Hunan Key of Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha 410022China

In the face of multiple challenges brought by the changes of global climate and environment,developing clean energy and updating green energy storage equipment are important ways to achieve carbon peak and carbon *** batteries have become a research hotspot due to their advantages of using the multivalent charge carrier,high ionic conductivity,environmental friendliness and cost *** this work,the Cu_(2)Se@C(Cu_(2)Se coated on carbon clothes)thin film with a three-dimensional braided structure is fabricated by a simple electrochemical deposition method for Cu^(2+)storage for the first *** with the commercial Cu_(2)Se powder,the well-designed Cu_(2)Se@C film shows enhanced specific capacity(640 mAh/g at 0.5 A/g)and rate performance(542 mAh/g at 5 A/g)as well as superior cycling stability(82.7%capacity retention after 1000 cycles at 1 A/g).The Cu^(2+)storage mechanism of the Cu_(2)Se@C electrode is based on a reversible phase transition process of Cu_(2)Se←→Cu_(2-x)Se←→CuSe←→CuSe_(2).In kinetic characteristic analysis,the Cu_(2)Se@C electrode demonstrates faster Cu^(2+)diffusion in discharge process than charge process resulting from the phase transition and the variation of interplanar *** work highlights a facile one-piece design strategy and opens a new gateway for the exploration of advanced aqueous energy storage systems.

关键词： Cu_(2)Se@C Cu^(2+)storage Conversion mechanism Kinetic characteristic Flexible energy storage

Diffuse Intrinsic Pontine Gliomas Exhibit Cell Biological and Molecular Signatures of Fetal Hindbrain-Derived Neural Progenitor Cells

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Neuroscience Bulletin 2019年第2期35卷 216-224页

作者： Yu Sun Cheng Xu Changcun Pan Xin Chen Yibo Geng Yuliang wu Peng Zhang wenhao wu Yu Wang Deling Li Zhen wu Junting Zhang Qiaoran Xi Liwei Zhang Department of Neurosurgery Beijing Tiantan HospitalCapital Medical University Ministry of Education Key Laboratory of Protein Sciences School of Life Sciences Tsinghua University

Diffuse intrinsic pontine glioma(DIPG) is the main cause of brain tumor-related death among *** now, there is still a lack of effective therapy with prolonged overall survival for this disease. A typical strategy for preclinical cancer research is to find out the molecular differences between tumor tissue and para-tumor normal tissue, in order to identify potential therapeutic targets. Unfortunately, it is impossible to obtain normal tissue for DIPG because of the vital functions of the *** we report the human fetal hindbrain-derived neural progenitor cells(pontine progenitor cells, PPCs) as normal control cells for DIPG. The PPCs not only harbored similar cell biological and molecular signatures as DIPG glioma stem cells, but also had the potential to be immortalized by the DIPG-specific mutation H3 K27 M in vitro. These findings provide researchers with a candidate normal control and a potential medicine carrier for preclinical research on DIPG.

关键词： Diffuse intrinsic pontine glioma Neural progenitor cells Immortalization H3K27M Senescence

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汽车级电子器件的标准与应用分析

电子技术（上海） 2024年第4期53卷 158-159页

作者：崔德胜宋航琪邬文浩陈朝杰高憬楠中国运载火箭技术研究院元器件可靠性中心北京100076

阐述无源元件标准体系及产品规范,分析AEC规范与国军标在抽样、试验项目、试验条件、失效判据中的差异及原因。探索汽车级无源元件标准对航天应用的可借鉴性。

关键词：计算机技术业务架构技术架构微服务拆分

Surficial modification enabling planar Al growth toward dendrite-free metal anodes for rechargeable aluminum batteries

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Science China Chemistry 2024年第4期67卷 1341-1351页

作者： wenhao Liu Yu Li Bo Long Haoyi Yang Lumin Zheng Ying Bai Feng wu Chuan wu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing 314019China

Al metal possesses ultrahigh theoretical volumetric capacity of 8,040 m Ah cm^(-3),and gravimetric capacity of 2,980 m Ah g^(-1),and thus is highly attractive for electrochemical energy ***,it suffers from several issues,such as the dendrite formation,during Al stripping-deposition cycling,which has been verified to account for the short circuit and limited cyclic ***,we use a facile and applicable method to in-situ reconstruct the Al anode surface with F-Al-O chemical bonds,which could preferentially induce the planar growth of Al along the interface plane,thus leading to the dendrite-free morphology evolution during the *** from F-Al-O chemical bonds on the surface of Al anodes,long lifespan of symmetric cells can be realized even under 1 m A cm^(-2)and 1 m Ah cm^(-2).Coupling the F-Al anode with graphite-based cathodes,high-voltage dual-ion Al metal batteries can be achieved with long-term cycle stability up to 1,200 cycles(at 0.5 m A cm^(-2)),surpassing the counterparts using pristine Al metal ***,the effectiveness of this surficial modification strategy is also elucidated with the aid of theoretical *** work provides novel insights on low-cost and facile strategies against the Al dendrite growth in aluminum batteries.

关键词： rechargeable aluminum batteries Al metal anode Al dendrite dual-ion batteries surficial modification

Unknown system dynamics estimator-based impedance control for lower limb exoskeleton with enhanced performance

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Control Theory and Technology 2024年第1期22卷 56-68页

作者： wenhao Zhang Peng Song Mingying wu Qiang Li Xinmin Mo Pingxin Ji Northwest Institute of Mechanical and Electrical Engineering Xianyang712099ShaanxiChina Xi’an Exo-Smart Dynamics Technology Ltd. Xi’an712046ShaanxiChina Department of Mechanical and Engineering Beijing Institute of TechnologyBeijing100081China

In this article, an unknown system dynamics estimator-based impedance control method is proposed for the lower limb exoskeleton to stimulate the tracking flexibility with the terminal target position when suffering parametric inaccuracies and unexpected disturbances. To reinforce the robust performance, via constructing the filtering operation-based dynamic relation, i.e., invariant manifold, the unknown system dynamics estimators are employed to maintain the accurate perturbation identification in both the hip and knee subsystem. Besides, a funnel control technique is designed to govern the convergence process within a minor overshoot and a higher steady-state precision. Meanwhile, an interactive complaint result can be obtained with the aid of the impedance control, where the prescribed terminal trajectory can be adjusted into the interaction variable-based target position by the force–position mapping, revealing the dynamic influence between the impedance coefficient (stiffness and damping) and the adjusted position magnitude. A sufficient stability analysis verifies the ultimately uniformly bounded results of all the error signals, and even the angle errors can be regulated within the predefined funnel boundary in the whole convergence. Finally, some simulations are provided to demonstrate the validity and superiority including the enhanced interaction flexibility and robustness.

关键词： Trajectory tracking Invariant manifold Funnel control Impedance control Lower limb exoskeleton