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铁路线路安全环境管控平台及试点应用

中国铁路 2024年第1期 169-174页

作者：张乐军马一丹庄文林高源中国铁路济南局集团有限公司电务部山东济南250000 北京全路通信信号研究设计院集团有限公司通信信号设计院北京100070

为满足铁路对外部环境、防洪防汛、险情、灾情、反恐治安等安全防范领域的高标准需求,国铁集团规划在全路统一建设“线路安全环境管控平台”。以济南局集团公司管控平台试点项目为例,梳理济南局集团公司既有视频监控系统现状,并深入剖... 详细信息

为满足铁路对外部环境、防洪防汛、险情、灾情、反恐治安等安全防范领域的高标准需求,国铁集团规划在全路统一建设“线路安全环境管控平台”。以济南局集团公司管控平台试点项目为例,梳理济南局集团公司既有视频监控系统现状,并深入剖析传统视频监控模式存在的问题;对管控平台国铁集团、铁路局集团公司2级架构建设模式进行论述,主要包括具体实现方式以及平台各功能模块;提出管控平台试点项目的建设方案,并总结先行试点应用中的不足,为后续全路全面推广和完善管控平台建设提供参考。

关键词：铁路线路巡防线路安全环境管控平台视频监控系统建设方案

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铁路通信承载网全光底座的组网结构与技术演进策略

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中国铁路 2024年第2期 122-126页

作者：高源张乐军马一丹庄文林北京全路通信信号研究设计院集团有限公司通信信号设计院北京100070 中国铁路济南局集团有限公司电务部山东济南250000

以光传送网(OTN)为代表的全光底座是当今通信承载网的基础,具备超大带宽、超低时延、安全可靠等优势,成为网络运力的基石。以济南局集团公司承载网的通信局干传输网为例,分析网络现状及组网结构存在的不足,重点围绕网络容量的持续增长... 详细信息

以光传送网(OTN)为代表的全光底座是当今通信承载网的基础,具备超大带宽、超低时延、安全可靠等优势,成为网络运力的基石。以济南局集团公司承载网的通信局干传输网为例,分析网络现状及组网结构存在的不足,重点围绕网络容量的持续增长、网络灵活调度等发展需求,论述铁路承载网全光底座组网结构的演进方向,并结合光业务单元(OSU)等新型承载技术发展和承载网局干OTN系统布局,提出总体规划思路,系统拓展了高铁线路大容量承载能力和业务综合性承载能力,同时也预留了向OSU灵活管道技术演进的能力,为构建铁路局集团公司承载网全光底座提供了规划方案和策略建议。

关键词：通信承载网局干传输网 OTN 全光底座 OSU

Equivariant Tautological Integrals on Flag Varieties

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Chinese Annals of Mathematics,Series B 2024年第3期45卷 463-486页

作者： Xiaobo zhuang Department of Mathematical Sciences Zhejiang Sci-Tech UniversityHangzhou 310018China

The author apples the Atiyah-Bott-Berline-Vergne formula to the equivariant tautological integrals over flag varieties of types A,B,C,D,and recovers the formulas expressing the integrals as iterated residues at infini... 详细信息

关键词： Localization Flag variety Residue

Cesium removal from radioactive wastewater by adsorption and membrane technology

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 161-175页

作者： Shuting zhuang Jianlong Wang School of Environment&Natural Resources Renmin University of ChinaBeijing 100872China Laboratory of Environmental Technology INETTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Radioactive Waste Treatment INETTsinghua UniversityBeijing 100084China

Radiocesium is frequently present in radioactive wastewater,while its removal is still a challenge due to its small hydrated radius,high diffusion coefficient,and similar chemical behavior to other alkali metal elements with high background *** review summarized and analyzed the recent advances in the removal of Cs+from aqueous solutions,with a particular focus on adsorption and membrane separation *** inorganic,organic,and biological adsorbents have undergone assessments to determine their efficacy in the removal of cesium ***,membrane-based separation techniques,including reverse osmosis,forward osmosis,and membrane distillation,have also shown promise in effectively separating cesium ions from radioactive ***,this review summarized the main approaches,including Kurion/SARRY system+desalination system and advanced liquid processing system,implemented after the Fukushima Daiichi nuclear power plant accident in Japan to remove radionuclides from contaminated *** technology and membrane separation technology play a vital role in treatment of contaminated water.

关键词： Cesium Adsorption Membrane separation Advanced liquid processing system Fukushima nuclear accident

Diverse atomic structure configurations of metal-doped transition metal dichalcogenides for enhancing hydrogen evolution

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Nano Research 2024年第5期17卷 3586-3602页

作者： Longlu Wang Yuxin Zhang Chen Gu Haoxuan Yu Yanling zhuang Zechao zhuang College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Jiangsu Province Engineering Research Center for Fabrication and Application of Special Optical Fiber Materials and DevicesNanjing University of Posts and TelecommunicationsNanjing 210023China Department of Chemical Engineering Columbia UniversityNew YorkNY 10027USA

Doping foreign metal atoms into the substrate of transition metal dichalcogenides(TMDs)enables the formation of diverse atomic structure configurations,including isolated atoms,chains,and ***,it is very important to reasonably control the atomic structure and determine the structure-activity relationship between the atomic configurations and the hydrogen evolution reaction(HER)*** numerous studies have indicated that doping can yield diverse atomic structure configurations,there remains an incomplete understanding of the relationship between atomic configurations within the lattice of TMDs and their ***,diverse atomic structure configurations of adsorptive doping,substitutional doping,and TMDs alloys are *** structure-activity relationship between different atomic configurations and HER performance can be determined by micro-nanostructure devices and density functional theory(DFT)*** diverse atomic structure configurations are of great significance for activating the inert basal plane of TMDs and improving the catalytic activity of ***,we have summarized the current challenges and future opportunities,offering new perspectives for the design of highly active and stable metal-doped TMDs catalysts.

关键词： transition metal dichalcogenides(TMDs) dopant effect diverse atomic structure configurations hydrogen evolution reaction(HER)

Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： Feng Ren zhuang-zhuang Liang Ming-Xin Niu Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic *** new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

A whole-net cooperative positioning method based on CDGNSS and inter-vehicle ranging

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Chinese Journal of Aeronautics 2024年第2期37卷 401-416页

作者： Shan HU Hongbo ZHAO Chen zhuang School of Electronics and Information Engineering Beihang UniversityBeijing 100191China

Relative positioning is recognized as an important issue for vehicles in urban ***-vehicle Cooperative Positioning(CP)techniques which fuse the Global Navigation Satellite System(GNSS)and inter-vehicle ranging have attracted attention in improving the performance of baseline estimation between ***,current CP methods estimate the baselines separately and ignore the interactions among the positioning information of different *** interactions are called’information coupling’.In this work,we propose a new multivehicle precise CP framework using the coupled information in the network based on the Carrier Differential GNSS(CDGNSS)and inter-vehicle *** demonstrate the benefit of the coupled information by deriving the Cramer-Rao Lower Bound(CRLB)of the float estimation in *** fully use this coupled information,we propose a Whole-Net CP(WN-CP)method which consists of the Whole-Net Extended Kalman Filter(WN-EKF)as the float estimation filter,and the Partial Baseline Fixing(PBF)as the ambiguity resolution *** WN-EKF fuses the measurements of all baselines simultaneously to improve the performance of float estimation,and the PBF strategy fixes the ambiguities of the one baseline to be estimated,instead of full ambiguity resolution,to reduce the computation load of ambiguity *** tests involving four vehicles were conducted in urban *** results show that the proposed WN-CP method can achieve better performance and meanwhile maintain a low computation load compared to the existing methods.

关键词： GNSS Cooperative positioning Baseline Ambiguity resolution Information coupling

Digital Twin Modeling Enabled Machine Tool Intelligence:A Review

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 29-54页

作者： Lei Zhang Jianhua Liu Cunbo zhuang School of Mechanical Engineering Tianjin University of CommerceTianjin 300134China Laboratory of Digital Manufacturing School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 10081China

Machine tools,often referred to as the“mother machines”of the manufacturing industry,are crucial in developing smart manufacturing and are increasingly becoming more *** twin technology can promote machine tool intelligence and has attracted considerable research ***,there is a lack of clear and systematic analyses on how the digital twin technology enables machine tool ***,digital twin modeling was identified as an enabling technology for machine tool intelligence based on a comparative study of the characteristics of machine tool intelligence and digital *** review then delves into state-of-the-art digital twin modelingenabled machine tool intelligence,examining it from the aspects of data-based modeling and mechanism-data dual-driven ***,it highlights three bottleneck issues facing the *** these problems,the architecture of a digital twin machine tool(DTMT)is proposed,and three key technologies are expounded in detail:Data perception and fusion technology,mechanism-data-knowledge hybrid-driven digital twin modeling and virtual-real synchronization technology,and dynamic optimization and collaborative control technology for multilevel ***,future research directions for the DTMT are *** work can provide a foundation basis for the research and implementation of digital-twin modeling-enabled machine tool intelligence,making it significant for developing intelligent machine tools.

关键词： Machine tool Digital twin Smart manufacturing Synchronization

An oscillation-free Hermite WENO scheme for hyperbolic conservation laws

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Science China Mathematics 2024年第2期67卷 431-454页

作者： zhuang Zhao Jianxian Qiu School of Mathematical Sciences and Institute of Natural Sciences Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computing Xiamen UniversityXiamen 361005China

In this paper, the sixth-order oscillation-free Hermite weighted essentially non-oscillatory (OFHWENO) scheme is proposed for hyperbolic conservation laws on structured meshes, where the zeroth- andfirst-order moments are the variables for the governing equations. The main difference from other HWENOschemes existing in the literature is that we add high-order numerical damping terms in the first-order momentequations to control spurious oscillations for the OF-HWENO scheme. The OF-HWENO scheme not only canachieve the designed optimal numerical order, but also can be easily implemented as we use only one set ofstencils in the reconstruction procedure and the same reconstructed polynomials are applied for the zeroth- andfirst-order moment equations. In order to obtain the adaptive order resolution when facing discontinuities, atransition polynomial is added in the reconstruction, where the associated linear weights can also be any positivenumbers as long as their summation equals one. In addition, the OF-HWENO scheme still keeps compactnessas only immediate neighbor values are needed in the space discretization. Some benchmark numerical tests areperformed to illustrate the high-order accuracy, high resolution and robustness of the proposed scheme.

关键词： Hermite WENO scheme hyperbolic conservation laws oscillation-free adaptive order discontinuous Galerkin method