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Polarimetric whitening filter for POLSAR image based on subspace decomposition

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Journal of Systems Engineering and Electronics 2008年第6期19卷 1121-1126页

作者： Yang Jian Deng Qiming Huangfu yue Zhang weijie Dept. of Electronics Engineering Tsinghua Univ. Beijing 100084 P. R. China

Speckle filtering is an indispensable pre-processing step for applications of polarimetric synthetic aperture radar （POLSAR）, such as terrain classification, target detection, etc. As one of the most typical methods, the polarimetric whitening filter （PWF） can be used to produce a minimum-speckle image by combining the complex elements of the scattering matrix, but polarimetric information is lost after the filtering process. A polarimetric filter based on subspaze decomposition which was proposed by Cu et al specializes in retrieving principle scattering characteristics, but the corresponding mean value of an image after filtering is not kept well. A new filter is proposed for improving the disadvantage based on subspace decomposition. Under the constraint that a weighted combination of the polarimetric SAR images equals to the output of the PWF, the Euclidean distance between an unfiltered parameter vector and a signal space vector is minimized so that noises can be reduced. It is also shown that the proposed method is equivalent to the subspace filter in the case of no constraint. Experimental results with the NASA/JPL airborne polarimetric SAR data demonstrate the effectiveness of the proposed method.

关键词： speckle filtering synthetic aperture radar polarimetric polarimetric whitening filter subspace decomposition

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面向人体动作视频的语义编码传输方法

移动通信 2024年第2期48卷 63-69页

作者：王沛辰岳伟杰党天健戴金晟牛凯北京邮电大学泛网无线通信教育部重点实验室北京100876

提出了一种高效的人体视频的无线传输方法,称为人体动作视频语义传输(AAST)系统。在当今的应用场景中,H.265视频编码和5GLDPC信道编码的组合已成为视频传输的常见方法。然而,在传输效率方面,尤其是在特殊情况下,仍存在相当大的提升潜力... 详细信息

提出了一种高效的人体视频的无线传输方法,称为人体动作视频语义传输(AAST)系统。在当今的应用场景中,H.265视频编码和5GLDPC信道编码的组合已成为视频传输的常见方法。然而,在传输效率方面,尤其是在特殊情况下,仍存在相当大的提升潜力。受到最近人体动作视频研究的进展启发,提出了AAST系统。AAST系统能够以高效的方式传输关键区域的语义信息,并在接收端重建原始视频。鉴于关键区域运动语义信息内在的相关性,AAST系统采用非线性分析变换将运动信息映射到潜在空间。然后通过信源信道联合编码,将运动信息的潜在表示传输到接收端。在该系统中,利用潜在表示的先验信息来估计关键区域语义信息的重要性。这有助于在信源信道联合编码中实现自适应码率控制,从而带来显著的编码增益。大量的实验证明了AAST系统相对于其他有竞争性的视频传输系统具有更卓越的性能。值得注意的是,与H.265视频编码和5GLDPC信道编码传输方法相比,在达到相同的感知指标时,AAST系统最高可以节省约70%的信道带宽,展现了其在视频无线传输中的鲁棒性。

关键词：语义通信人体动作视频信源信道联合编码变分模型

Quantum Spin Exchange Interactions to Accelerate the Redox Kinetics in Li–S Batteries

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Nano-Micro Letters 2024年第5期16卷 370-383页

作者： Yu Du weijie Chen Yu Wang yue Yu Kai Guo Gan Qu Jianan Zhang Key Laboratory of Advanced Energy Catalytic and Functional Materials Preparation of Zhengzhou City College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001People’s Republic of China

Spin-engineering with electrocatalysts have been exploited to suppress the“shuttle effect”in Li–S *** selec-tion,spin-dependent electron mobility and spin potentials in activation barriers can be optimized as quantum spin exchange interactions lead-ing to a significant reduction of the electronic repulsions in the orbitals of ***,we anchor the MgPc molecules on fluorinated carbon nanotubes(MgPc@FCNT),which exhibits the single active Mg sites with axial *** to the density functional theory calculations,the electronic spin polarization in MgPc@FCNT not only increases the adsorption energy toward LiPSs intermediates but also facilitates the tunneling process of electron in Li–S *** a result,the MgPc@FCNT provides an initial capacity of 6.1 mAh cm^(-2) even when the high sulfur loading is 4.5 mg cm^(-2),and still maintains 5.1 mAh cm^(-2) after 100 *** work provides a new perspective to extend the main group single-atom catalysts enabling high-performance Li–S batteries.

关键词： Metal phthalocyanines Spin polarization Electrocatalysis Li–S batteries

Ling-Ling Chen: RNA has its own features;don't study it as a protein

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National Science Review 2024年第2期11卷 301-305页

作者： weijie Zhao NSR

Non-coding RNA(ncRNA) has been a very active research area over the past 30 years. From small nc RNA – the discovery of RNA interference won the lead researchers the Nobel Prize, to long ncRNA(lncRNA), which has attracted much attention in recent years, various nc RNAs participate in all kinds of biological processes and show a variety of biomedical application prospects.

关键词： RNA

Meeting the challenges of invasive alien species

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National Science Review 2024年第3期11卷 296-298页

作者： weijie Zhao NSR news

The Xinjiang Uygur Autonomous Region of China is famous for its tomato production. Abundant sunshine, large day–night temperature difference and the abundant irrigation by snowmelt from the Tianshan Mountains produce...

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基于“一滴油旅程”的风险辨识及应用

化工管理 2024年第15期 113-116页

作者：岳炜杰王进周建良宋天伟刘全军刘博勋中航油(北京)机场航空油料有限责任公司北京102600

近年来,国家应急管理部门对重大危险源风险监管力度逐渐提高,为积极贯彻落实习近平总书记关于安全生产的重要论述以及对民航安全工作的重要指示批示精神,中航油(北京)机场航空油料有限责任公司在加强安全管理的同时,持续加强安全文化建... 详细信息

近年来,国家应急管理部门对重大危险源风险监管力度逐渐提高,为积极贯彻落实习近平总书记关于安全生产的重要论述以及对民航安全工作的重要指示批示精神,中航油(北京)机场航空油料有限责任公司在加强安全管理的同时,持续加强安全文化建设,提升风险辨识能力。航空供油部以“一滴油旅程”为线索,开展全过程的风险辨识。通过分级管控,梳理出高发时段、重点岗位以及针对性措施,确保风险得到有效规避,提高安全生产水平。“一滴油旅程”风险辨识工作已顺利开展,并成功与双重预防机制建设有机结合,构建完善的包含安全风险分级管控和隐患排查治理的双重预防机制。这一机制已应用于油库常态化风险管理,有效提高了风险防范能力。

关键词：风险辨识隐患排查双重预防机制油库

标准化作业程序在可持续航空燃料调合稀释过程中的研究与应用

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化工管理 2024年第24期 1-3,33页

作者：刘博勋王进周建良岳炜杰刘全军白青松中航油(北京)机场航空油料有限责任公司北京102600

文章旨在探究标准化作业程序在可持续航空燃料调合稀释过程中的应用。通过对相关标准化作业指导手册和民用航空燃料相关行业标准的深入研究,结合实际生产作业过程,文章概括了可持续航空燃料生产过程中最为重要的调合与稀释步骤的作业流... 详细信息

文章旨在探究标准化作业程序在可持续航空燃料调合稀释过程中的应用。通过对相关标准化作业指导手册和民用航空燃料相关行业标准的深入研究,结合实际生产作业过程,文章概括了可持续航空燃料生产过程中最为重要的调合与稀释步骤的作业流程,实现了生产过程精确化、标准化,从而形成了一套实用性强、参考性高、流程明晰的可持续航空燃料调合和稀释的标准化作业程序,得出了相关结论并提出了具体的应用建议,旨在为相关领域的研究和实践提供参考。

关键词：可持续航空燃料碳中和标准化作业程序调和稀释油库

When mRNA meets gene editing

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Nano Research 2024年第8期17卷 7337-7356页

作者： weijie Li Chen Wang Yuan Lu Key Laboratory of Industrial Biocatalysis Ministry of EducationDepartment of Chemical EngineeringTsinghua UniversityBeijing 100084China Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

The critical challenge of gene therapy lies in delivering gene editing *** with DNA,while RNA is less stable and more accessible to degrade,it comes with the benefit of lower off-target effects since permanent insertion is not *** review focuses on mRNA-based delivery of gene editing agents,highlighting novel mRNA delivery *** provide context,a comparison is made between three main gene editing agents:programmable nucleases,base editors,and prime *** potential of Cas\pi and transposons is also discussed in this ***,a summary of four main barriers to mRNAbased in vivo delivery is ***,this review detailedly introduced different delivery systems,both viral(lentivirus)and non-viral vectors(genome editing via oviductal nucleic acids delivery,lipid nanoparticles,polymer-based nanoparticles,viruslike-particles,extracellular vesicles,and migrasome).Each delivery strategy is assessed by comparing its advantages and disadvantages to offer a comprehensive and objective overview of the delivery ***,we emphasized the vital role of the protein corona as a critical regulator for ***,we concluded the challenges of mRNA-based gene editing strategies(RNA stability,targeting,potential immunogenicity,cytotoxicity,heterogeneity,and rational design).The purpose of this review is to guide further research and provide a comprehensive analysis of mRNA-based in vivo delivery of gene editing agents in this promising field.

关键词： gene editing mRNA delivery viral vectors non-viral vectors CRISPR

Conceptual design and control method for a noncontact annular electromagnetic stabilized satellite platform

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Chinese Journal of Aeronautics 2024年第1期37卷 256-270页

作者： He LIAO Daixin WANG Yuan REN weijie WANG Institute of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 211106China Department of Basic Course Space Engineering UniversityHuairou DistrictBeijing 101416China

Disturbance-Free Payload(DFP)spacecraft can meet the requirements of ultra-high attitude pointing accuracy and stability for future space ***,as the main control actuators of DFP spacecraft,Linear Non-Contact Lorentz Actuators(LNCLAs)have control output problems with six-degree-of-freedom coupling and nonlinear effects,which will affect the attitude control performance of DFP *** solve this problem,a novel concept for Non-Contact Annular Electromagnetic Stabilized Satellite Platform(NCAESSP)is proposed in this *** concept is centered on replacing the LNCLAs with a non-contact annular electromagnetic actuator to solve the two problems mentioned ***,for the different control requirements of the payload module and the support module of the NCAESSP,a high-precision attitude controller based on the robust model matching method and a dual quaternion-based adaptive sliding mode controller are ***,the simulation results verify the feasibility and effectiveness of the proposed approach.

关键词： Disturbance-free payload Robust model matching Dual quaternion Sliding mode control Collision avoidance