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Decycling Number of Type-k Halin Graphs

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Journal of Mathematical Research with Applications 2025年第2期 143-151页

作者： Wanjia ZHANG Chao YANG Han ren School of Mathematics and Physics Xinjiang Hetian College School of Mathematics Physics and Statistics Shanghai University of Engineering Science School of Mathematical Sciences East China Normal University

A set S of vertices of a graph G is called a decycling set if G-S is *** smallest size of a decycling set is called the decycling number of G and is denoted by?(G).In this paper,we investigate the decycling number of type-k Halin graphs,focusing on those that are formed from trees that have just two degrees k and *** any type-k Halin graph G of order n,we prove that■The result not only supports the largest forest conjecture due to Albertson and Berman (1976),but also offers a tight lower bound for the decycling number of type-3 Halin graphs and several type-k Halin ***,a new formula to determine the cardinality of any decycling set S of a type-k Halin graph G is provided.

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Mathematical Analysis and Simulation of Secure Information Transmission and Processing Model

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China Communications 2025年第03期 181-201页

作者： ren Quan Wu Jiangxing He Lei Information Engineering University

The security of information transmission and processing due to unknown vulnerabilities and backdoors in cyberspace is becoming increasingly problematic. However, there is a lack of effective theory to mathematically demonstrate the security of information transmission and processing under nonrandom noise(or vulnerability backdoor attack) conditions in cyberspace. This paper first proposes a security model for cyberspace information transmission and processing channels based on error correction coding theory. First, we analyze the fault tolerance and non-randomness problem of Dynamic Heterogeneous Redundancy(DHR) structured information transmission and processing channel under the condition of non-random noise or attacks. Secondly,we use a mathematical statistical method to demonstrate that for non-random noise(or attacks) on discrete memory channels, there exists a DHR-structured channel and coding scheme that enables the average system error probability to be arbitrarily small. Finally, to construct suitable coding and heterogeneous channels, we take Turbo code as an example and simulate the effects of different heterogeneity, redundancy,output vector length, verdict algorithm and dynamism on the system, which is an important guidance for theory and engineering practice.

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An equivariant index theorem on R~n in the context of continuous fields of C*-algebras

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Science China Mathematics 2025年

作者： Baiying ren Hang Wang Zijing Wang Research Center for Operator Algebras School of Mathematical SciencesEast China Normal University

We prove an equivariant index theorem on the Euclidean space using a continuous field of C*-algebras. This generalizes the work of Elliott et al.（1996）, which is a special case of the algebraic index theorem by Nest and Tsygan （1995）. Using our formula, we see that the equivariant index of the Bott-Dirac operator on R2ncan be explicitly calculated.

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Carbody sway behaviour of railway vehicles due to track irregularity from rail alternate side wear

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Railway Engineering Science 2025年第1期33卷 27-42页

作者： Lai Wei Jing Zeng ren Luo Feng Gan Jijun Gong Jun Jiang State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China China Railway Materials Operation and Maintenance Technology Co.Ltd. Beijing 100071China

Track irregularity from rail alternate side wear is manifested as uneven rail wear waveforms alternating in the left and right rails with equal intervals,which will cause carbody sway behaviour of railway vehicles and greatly influences the passenger *** this work,the carbody sway behaviour and mechanism due to track irregularity from rail alternate side wear and possible solutions to this issue were studied by the field testing and numerical calculation ***,the carbody sway of an urban rail transit train is introduced with full-scale field tests,through which the rail alternate side wear is characterized and the formatted track irregularity are ***,multibody vehicle dynamic models are developed to reproduce the carbody sway behaviour induced by the track irregularity from the rail alternate side *** creep forces acting on the wheel and rail are preliminarily discussed to study the influence of the carbody sway on the wear of the wheel flange and the rail ***,some potential solutions,*** the damping ratio of carbody rigid mode and rail grinding,are proposed to relieve this *** is concluded that an increased damping ratio of the carbody mode can alleviate the carbody sway and wheel–rail interactions,while properly maintaining track conditions can improve the vehicle performance.

关键词： Carbody sway Track irregularity Rail wear Creep force Carbody mode

酒精依赖和戒断时大鼠伏隔核、杏仁核区内神经甾体水平的变化

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中国药物依赖性杂志 2007年第1期16卷 20-25页

作者：任进民闫彩珍侯艳宁河北医科大学白求恩国际和平医院石家庄050082

目的:采用♂大鼠酒精依赖模型,观察酒精依赖及戒断对大鼠伏隔核、杏仁核中不同神经甾体水平的影响。方法:通过大鼠自由饮含6%的乙醇溶液,连续42d使大鼠形成酒精依赖,并撤除酒精使其自然戒断。断头取脑分离取出伏隔核、杏仁核脑区。使用... 详细信息

目的:采用♂大鼠酒精依赖模型,观察酒精依赖及戒断对大鼠伏隔核、杏仁核中不同神经甾体水平的影响。方法:通过大鼠自由饮含6%的乙醇溶液,连续42d使大鼠形成酒精依赖,并撤除酒精使其自然戒断。断头取脑分离取出伏隔核、杏仁核脑区。使用液液萃取和固相萃取两步法提取脑组织中的孕烯醇酮(PREG)、脱氢表雄酮(DHEA)、别孕烯醇酮(AP)、脱氢表雄酮硫酸酯(DHEAS)、孕烯醇酮硫酸酯(PREGS),以高效液相色谱-质谱联用法测定神经甾体含量。结果:与对照组相比,酒精依赖大鼠伏隔核DHEA,PREG,AP,DHEAS,PREGS的水平显著降低(P<0.05),杏仁核AP,PREGS的水平显著降低(P<0.05);酒精戒断6h大鼠伏隔核DHEA,DHEAS,PREGS的水平显著降低(P<0.05),杏仁核PREGS的水平显著降低(P<0.05);酒精戒断24h大鼠杏仁核DHEA的水平显著上升(P<0.05),伏隔核、杏仁核DHEAS、PREGS的水平显著下降(P<0.01)。结论:酒精依赖形成和戒断对伏隔核、杏仁核中的神经甾体水平有不同的影响,具有区域特异性。

关键词：酒精依赖戒断神经甾体伏隔核杏仁核

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Updates to the 2024 CSCO advanced non-small cell lung cancer guidelines

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Cancer Biology & Medicine 2025年第02期 77-82页

作者： Jiale Wang Tianyu Qiu Shengxiang ren School of Medicine Tongji University Department of Medical Oncology Shanghai Pulmonary Hospital School of Medicine Tongji University

In the past year, several advancements have been achieved in the treatment of advanced non-small cell lung cancer(NSCLC), particularly in the areas of immunotherapy and targeted therapy. These achievements have provided additional options for improving patient outcomes. The 2024 Chinese Society of Clinical Oncology Guidelines for NSCLC (CSCO NSCLC), a key reference for clinical oncologists in China, have incorporated current global research and adapted recommendations for applicability in real-world scenarios in China. This update covers not only patient selection, efficacy, and safety,but also considers economics, and accessibility, with an aim to provide more precise and comprehensive treatment guidance for Chinese oncologists.

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Future development research of 5G positioning in 3GPP standards

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The Journal of China Universities of Posts and Telecommunications 2025年

作者： Liu Wen ren Hailong Deng Zhongliang School of Electronic Engineering， Beijing University of Posts and Telecommunications

Since the release of the first version of the 5th Generation Mobile Networks (5G) standard， Release-15 (Rel-15)， in June 2018， the 3rd Generation Partnership Project (3GPP) made significant efforts in the field of indoor and outdoor wireless positioning. Notably， Release-16 augmented support for enhanced mobile broadband (eMBB) and ultra-reliable low-latency communication (uRLLC)， particularly within complex indoor settings. To further meet the diverse application needs of positioning scenarios， the 3GPP standards for Release-17 and Release-18 propose new enhancement measures to continuously provide more accurate positioning services. In this paper， the scholarly discourse on 5G positioning was critically examined， providing a systematic review of the 5G positioning standards as delineated in 3GPP's Release-16 and Release-17， and was extended the discussion to the anticipated enhancements in 5G Release-18， along with their underlying motivations. Through these discussions， this article not only a comprehensive perspective on the current development of 5G positioning technology was provided but also was offered forward-looking analysis and predictions for the evolution of positioning technology in the upcoming 3GPP Release-19 phase. Additionally， it serves as a reference for researchers interested in understanding the development of positioning within the standard framework in the field of 5G indoor positioning， which holds significant meaning for promoting research and application of 5G positioning technology.

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An Objective Synoptic Analysis Technique for the Identification of Tropical Cyclone Remote Precipitation in China and Its Application

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Journal of Ocean University of China 2025年第1期24卷 13-30页

作者： JIA Li DING Chenchen CONG Chunhua ren Fumin LIU Yanan School of Atmospheric Science Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Public Meteorological Service Center of CMA Beijing 100081China Shandong Meteorological Bureau Jinan 250031China Laboratory of Cloud-Precipitation Physics and Severe Storms(LACS) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

At present,the identification of tropical cyclone remote precipitation(TRP)requires subjective participation,leading to inconsistent results among different researchers despite adopting the same identification ***,establishing an objective identification method is greatly *** this study,an objective synoptic analysis technique for TRP(OSAT_TRP)is proposed to identify TRP using daily precipitation datasets,historical tropical cyclone(TC)track data,and the ERA5 reanalysis *** method includes three steps:first,independent rain belts are separated,and those that might relate to TCs'remote effects are distinguished according to their distance from the ***,the strong water vapor transport belt from the TC is identified using integrated horizontal water vapor transport(IVT).Third,TRP is distinguished by connecting the first two *** TRP obtained through this method can satisfy three criteria,as follows:1)the precipitation occurs outside the circulation of TCs,2)the precipitation is affected by TCs,and 3)a gap exists between the TRP and TC rain *** diagnosis analysis,compared with subjective TRP results and backward trajectory analyses using HYSPLIT,indicates that OSAT_TRP can distinguish TRP even when multiple TCs in the Northwest Pacific are ***,we applied the OSAT_TRP to select typical TRPs and obtained the synoptic-scale environments of the TRP through composite analysis.

关键词： tropical cyclone remote precipitation objective identification method

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Oxygen vacancies-rich molybdenum tungsten oxide nanowires as a highly active nitrogen fixation electrocatalyst

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Chinese Chemical Letters 2025年第1期36卷 545-548页

作者： Jincheng Zhang Mengjie Sun Jiali ren Rui Zhang Min Ma Qingzhong Xue Jian Tian School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Herein,vacancy engineering is utilized reasonably to explore molybdenum tungsten oxide nanowires(W_(4)MoO_(3)NWs)rich in O-vacancies as an advanced electrochemical nitrogen reduction reaction(eNRR)electrocatalyst,realizing further enhancement of NRR *** 0.1 mol/L Na_(2)SO_(4),W_(4)MoO_(3)NWs rich in O vacancies(CTAB-D-W_(4)MoO_(3))achieve a large NH3yield of 60.77μg h^(-1)mg^(-1)***-0.70 V *** and a high faradaic efficiency of 56.42%at-0.60 V,much superior to the W_(4)MoO_(3)NWs deficient in oxygen vacancies(20.26μg h^(-1)mg^(-1)*** 17.1%at-0.70 V ***).Meanwhile,W_(4)MoO_(3)NWs rich in O-vacancies also show high electrochemical *** functional theory(DFT)calculations present that O vacancies in CTAB-D-W_(4)MoO_(3)reduce the energy barrier formed by the intermediate of^(*)N-NH,facilitate the activation and further hydrogenation of^(*)N-N,promote the NRR process,and improve NRR activity.

关键词： Electrocatalytic N_(2) reduction reaction Molybdenum-tungsten oxide Nanowires Oxygen vacancies Non-noble metal

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