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Key Technologies for AI-Driven Network Traffic Classification Workflow and Data Distribution Shift
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作者 Zhao Jianchao Geng Zhaosen +1 位作者 Li Zeyi Wang Pan 《ZTE Communications》 2026年第1期34-44,共11页
With the evolution of next-generation network technologies,the complexity of network management has significantly increased,and the means of network attacks are diversified,bringing new challenges to network traffic c... With the evolution of next-generation network technologies,the complexity of network management has significantly increased,and the means of network attacks are diversified,bringing new challenges to network traffic classification.This paper presents a general AIdriven network traffic classification workflow and elaborates on a traffic data and feature engineering framework.Most importantly,it analyzes the concept and causes of data distribution shifts in ne twork traffic,proposing detection methods and countermeasures.Experimental results on real traffic collected at different time intervals show that application evolution can induce data distribution shifts,which in turn lead to a noticeable degradation in traffic classification performance.Comparative drift detection experiments further confirm that such shifts are more evident over long-term intervals,while short-term traffic remains relatively stable.These findings demonstrate the necessity of incorporating drift-aware mechanisms into AI-driven network traffic classification systems. 展开更多
关键词 traffic classification traffic identification deep learning data distribution shift concept shifting
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Efficient Model Reduction of Linear Time-varying Systems via Shifted Legendre Polynomial Approximations
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作者 XIAO Zhihua TANG Man ZHU Zhihui 《应用数学》 北大核心 2026年第2期481-493,共13页
This paper presents an efficient model reduction technique for linear time-varying systems based on shifted Legendre polynomials.The approach constructs approximate low-rank decomposition factors of finite-time Gramia... This paper presents an efficient model reduction technique for linear time-varying systems based on shifted Legendre polynomials.The approach constructs approximate low-rank decomposition factors of finite-time Gramians directly from the expansion coefficients of impulse responses.Leveraging these factors,we develop two model reduction algorithms that integrate the low-rank square root method with dominant subspace projection.Our method is computationally efficient and flexible,requiring only a few matrix-vector operations and a singular value decomposition of a low-dimensional matrix,thereby avoiding the need to solve differential Lyapunov equations.Numerical experiments confirm the effectiveness of the proposed approach. 展开更多
关键词 Model reduction Time-varying systems Low-rank Gramians Balanced truncation shifted Legendre polynomials
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Predicting the impacts of climate change on the distribution of rare Meconopsis species in China:Habitat shifts and conservation implications
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作者 Siteng Jiang Renwu Wu +4 位作者 Min Wu Jiachen Liu Hai Yan Wenbin Nie Zhiyi Bao 《Ecological Frontiers》 2026年第1期82-107,共26页
As global climate change intensifies,alpine plants are facing dual pressures of habitat loss and rapid environmental degradation.As one of the world's most biodiverse countries,China's potential shifts in alpi... As global climate change intensifies,alpine plants are facing dual pressures of habitat loss and rapid environmental degradation.As one of the world's most biodiverse countries,China's potential shifts in alpine plant distribution and their profound impact on fragile ecosystems have become a focus of ecological research and conservation efforts,with increasing urgency.Meconopsis,a typical representative of Chinese alpine plants,exhibits diverse adaptability,making it an ideal model for studying how alpine species respond to extreme environmental changes.A lack of comprehensive genus-level analyses may hinder the development of long-term conservation and management strategies.Given the genus's ecological importance,vulnerability,and the risk of trait homogenization in genus-level modeling,there is an urgent need to assess its future distribution patterns,migration trends,and adaptive mechanisms based on habitat classification.In this study,we employed the Maxent model,integrating multidimensional environmental variables,to develop genus-level models and representative habitat-based models(forest,meadows,and periglacial).Results indicate a northwestward expansion and southeastward contraction of suitable habitats under future climate scenarios,with migration patterns in latitude and elevation showing stage-specific characteristics.Key environmental factors varied across models but were mostly associated with seasonal growth traits and microhabitat conditions,highlighting both the universal ecological requirements and niche differentiation within Meconopsis.Based on these findings,we propose a dynamic conservation strategy framework informed by stage-specific responses and habitat differences.Future efforts should focus on incorporating alpine-specific environmental variables and optimizing specimen collection strategies to enhance model performance and support landscape planning and biodiversity conservation. 展开更多
关键词 Alpine plants Climate change Habitat shift Meconopsis Species distribution
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Decadal shift in Northeast China’s precipitation around 2000
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作者 Yawen Liao Tianbao Zhao +1 位作者 Jingpeng Zhang Yankun Sun 《Atmospheric and Oceanic Science Letters》 2026年第1期14-21,共8页
Northeast China(NEC),a critical agricultural and ecological zone,has experienced intensified hydrological variability under global warming,with cascading impacts on food security and ecosystem resilience.This study ut... Northeast China(NEC),a critical agricultural and ecological zone,has experienced intensified hydrological variability under global warming,with cascading impacts on food security and ecosystem resilience.This study utilized observational data and two new generation reanalysis products(i.e.,the fifth major global reanalysis produced by ECMWF(ERA5)and the Japanese Reanalysis for Three Quarters of a Century(JRA-3Q))to investigate the shift changes in precipitation in NEC around 2000 and associated water vapor transport.The analysis identified a pivotal interdecadal shift in 1998/99,transitioning from moderate increases(17.5 mm/10 yr during 1980-1998)to accelerated but more variable precipitation growth(85.4 mm/10 yr post-1999).While the mean precipitation during the post-shift period decreased,enhanced anticyclonic circulation amplified moisture divergence over continental NEC,redirecting vapor flux toward coastal regions.Crucially,trajectory analysis demonstrated regime-dependent moisture sourcing:midlatitude westerlies dominated during wet extremes(44% of trajectories in 1998),whereas East Asian monsoon flows prevailed in drought years(36% of trajectories in 2007).The post-1998 period exhibited increased reliance on localized recycling(45%of mid-tropospheric trajectories),reflecting weakened monsoonal inflow.These findings highlight NEC’s growing vulnerability to competing moisture pathways and atmospheric blocking-a dual mechanism that explains rising extremes despite declining mean precipitation.By reconciling dataset discrepancies(ERA5 vs.JRA-3Q trends)and elucidating circulation-precipitation linkages,this work provides actionable insights for climate-resilient agriculture in NEC’s water-stressed ecosystems. 展开更多
关键词 PRECIPITATION Decadal shift Water vapor transport Northeast China
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Towards a universal ansatz for heat-induced emission peak shifts:insights from M_(2)SiO_(4):Eu^(2+)(M=Sr,Ba,Ca)phosphors
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作者 Shijie Chen Zul Qarnain +4 位作者 Xiyue Cheng Zhian Li Guoliang Liu Zhuoling Jiang Shuiquan Deng 《Materials Futures》 2026年第2期194-208,共15页
Heat-induced emission peak shift(HIEPS),encompassing both redshift and blueshift,remains mechanistically unresolved in phosphor materials.Using state-of-the-art first-principles calculations of M_(2)SiO_(4):Eu^(2+)(M=... Heat-induced emission peak shift(HIEPS),encompassing both redshift and blueshift,remains mechanistically unresolved in phosphor materials.Using state-of-the-art first-principles calculations of M_(2)SiO_(4):Eu^(2+)(M=Sr,Ba,Ca),we reveal that conventional thermal expansion theory cannot adequately explain these phenomena.Instead,our frozen phonon analysis identifies local electron-phonon coupling as the dominant mechanism,where anisotropic thermal vibrations selectively distort the asymmetric Eu-5d potential well that arises from the dopant’s coordination environment.This distortion manifests through the temperature-sensitiveΔ_(f−d) parameter governing the 5d→4f transition energy,directly controlling spectral shifts.Our findings establish a universal framework for HIEPS in rare-earth phosphors and enable a Δ_(f−d)-guided strategy for designing thermally stable phosphors. 展开更多
关键词 electron-phonon coupling PHOSPHORS first-principles calculations frozen phonon heat-induced emission peak shift
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Survey Analysis of Traditional Chinese Medicine Constitution Among Night Shift Nurses in a Public Grade A Tertiary Hospital
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作者 Ting Li Jia Jiang Wendan Sun 《Journal of Clinical and Nursing Research》 2026年第2期115-121,共7页
Objective:To investigate the distribution of Traditional Chinese Medicine(TCM)constitution among night-shift nurses at a public tertiary-level Class A hospital,thereby identifying new approaches for developing effecti... Objective:To investigate the distribution of Traditional Chinese Medicine(TCM)constitution among night-shift nurses at a public tertiary-level Class A hospital,thereby identifying new approaches for developing effective interventions to enhance their health status.Methods:A total of 601 nurses employed at a public tertiary-level Class A hospital from August 2024 to August 2025 participated in the survey.Analysis was conducted using the Traditional Chinese Medicine Constitution Questionnaire.Results:The most prevalent TCM constitution types among night-shift nurses were Yang Deficiency Constitution(50.4%),Yin Deficiency Constitution(49.8%),Qi Deficiency Constitution(45.4%),and Phlegm-Dampness Constitution(45.1%).Conclusion:A high proportion of clinical night-shift nursing staff exhibit imbalanced constitution types,severely impacting their physical and mental health.Nursing administrators should implement targeted TCM constitution-based health maintenance and regulation to improve the health status of nursing personnel. 展开更多
关键词 Night shift Nurses TCM constitution identification
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From Index Evaluation to Intelligent Sensing:Paradigm Shift in Research on Tourism Climate Comfort and Prospects under Technological Enabling
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作者 Xiao WANG 《Meteorological and Environmental Research》 2026年第1期29-31,共3页
Research on tourism climate comfort is undergoing a paradigm shift from classic static assessment to intelligent dynamic sensing.Early models(such as temperature-humidity index and tourism climate index)established ba... Research on tourism climate comfort is undergoing a paradigm shift from classic static assessment to intelligent dynamic sensing.Early models(such as temperature-humidity index and tourism climate index)established based on data of meteorological stations laid the foundation for the discipline but were unable to meet the dynamic demands of climate change,spatial heterogeneity,and individual experience.Global climate change is reshaping the landscape of tourism comfort and driving the assessment to shift towards future risk prediction.Downscaling technology becomes the key to connecting global scenarios and local assessments.Remote sensing and Internet of Things technologies have constructed a"sky-ground"collaborative sensing network,achieving a revolution in data acquisition.Artificial intelligence and big data analysis serve as the intelligent core to drive research from description to prediction.The new paradigm has significant potential in improving assessment accuracy and timeliness,but also faces challenges such as data integration,model interpretability,interdisciplinary integration,and ethical privacy.In the future,it is needed to develop interpretable AI,construct climate digital twins,and promote full-chain coupling research.This transformation is not merely an upgrade of methods,but a fundamental shift in the study of philosophy from an"environment-centered"perspective to an"experience-centered"one,providing key scientific support for sustainable tourism. 展开更多
关键词 Tourism climate comfort Paradigm shift Climate change Remote sensing Internet of Things Artificial intelligence
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Prolonged Sleep Deprivation Induces Cochlear Synaptopathy and Temporary Threshold Shift via the TLR4/NF-κB/NLRP3 Signaling Pathway
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作者 Xiaoqiong Song Kefeng Ma +6 位作者 Mengzhu Cheng Cui Gu Fenghan Wang Xinyu Dai Chunping Wang Xiaojun She Bo Cui 《Biomedical and Environmental Sciences》 2026年第3期368-374,共7页
Sleep is a biological phenomenon with highly conserved evolutionary characteristics.The American Academy of Sleep Medicine and the Sleep Research Society recommend that adults get at least 7 hours of sleep per night[1... Sleep is a biological phenomenon with highly conserved evolutionary characteristics.The American Academy of Sleep Medicine and the Sleep Research Society recommend that adults get at least 7 hours of sleep per night[1].However,the stress caused by fast-paced life often leads to sleep deprivation(SD).SD is strongly associated with damage to the auditory system[2,3].Obstructive sleep apnea-hypopnea syndrome(OSAHS)is a common sleep disorder.Clinical observations indicate that some patients with OSAHS experience persistent hearing loss accompanied by tinnitus and other symptoms[4].More than 61.8%of patients with sudden deafness experienced SD[5]. 展开更多
关键词 TLR sleep deprivation temporary threshold shift sleep deprivation sd sd sleep disorderclinical auditory system NF B cochlear synaptopathy
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Three Shifts That Will Redefine Health Systems
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作者 You Wu Haibo Wang Zongjiu Zhang 《Health Care Science》 2026年第1期1-3,共3页
Academic journals,consulting firms,and mainstream media have often published“predictions”about the future develop-ment of medical and health care.These publications often emphasize the potential of cutting-edge scie... Academic journals,consulting firms,and mainstream media have often published“predictions”about the future develop-ment of medical and health care.These publications often emphasize the potential of cutting-edge scientific or technical breakthroughs.Health Care Science looks at the problem from another perspective.We focus on how these changes enter the health system,how they operate in the real world,and how they reshape the organization and governance of medical services.At the beginning of 2026,we envision the following three major shifts that will reshape healthcare. 展开更多
关键词 academic journals health systems health care science mainstream media shiftS cutting edge scientific technical breakthroughs consulting firms
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A Strategic Shift:Two Sessions reaffirm China’s commitment to high-quality development and global opportunities
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作者 HU FAN 《ChinAfrica》 2026年第4期16-17,共2页
At the start of China’s 15th Five-Year Plan period(2026–2030),signals from March’s Two Sessions point to a subtle but notable change in direction.Policymakers are moving beyond an emphasis on headline growth figure... At the start of China’s 15th Five-Year Plan period(2026–2030),signals from March’s Two Sessions point to a subtle but notable change in direction.Policymakers are moving beyond an emphasis on headline growth figures and are instead concentrating on building a more resilient economic foundation in a volatile global environment. 展开更多
关键词 economic resilience strategic shift two sessions building more resilient economic foundation global opportunities volatile global environment th five year plan high quality development
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A theoretical study of the role of K on the reverse water-gas shift reaction on Hägg carbide 被引量:1
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作者 Xianxuan Ren Rozemarijn D.E.Krösschell +3 位作者 Zhuowu Men Peng Wang Ivo A.W.Filot Emiel J.M.Hensen 《Chinese Journal of Catalysis》 2025年第5期289-300,共12页
Potassium(K)is known to enhance the catalytic performance of Fe-based catalysts in the reverse water-gas shift(rWGS)reaction,which is highly relevant during Fischer-Tropsch(FT)synthesis of CO_(2)-H_(2) mixtures.To elu... Potassium(K)is known to enhance the catalytic performance of Fe-based catalysts in the reverse water-gas shift(rWGS)reaction,which is highly relevant during Fischer-Tropsch(FT)synthesis of CO_(2)-H_(2) mixtures.To elucidate the mechanistic role of K promoter,we employed density functional theory(DFT)calculations in conjunction with microkinetic modelling for two representative surface terminations of Hägg carbide(χ-Fe_(5)C_(2)),i.e.,(010)and(510).K_(2)O results in stronger adsorption of CO_(2)and H_(2) on Hägg carbide and promotes C–O bond dissociation of adsorbed CO_(2)by increasing the electron density on Fe atoms close to the promoter oxide.The increased electron density of the surface Fe atoms results in an increased electron-electron repulsion with bonding orbitals of adsorbed CO_(2).Microkinetics simulations predict that K_(2)O increases the CO_(2)conversion during CO_(2)-FT synthesis.K_(2)O also enhances CO adsorption and dissociation,facilitating the formation of methane,used here as a proxy for hydrocarbons formation during CO_(2)-FT synthesis.CO dissociation and O removal via H_(2)O compete as the rate-controlling steps in CO_(2)-FT. 展开更多
关键词 Fischer-Tropsch synthesis Hägg carbide Reverse water-gas shift Potassium Density functional theory
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Random forest algorithm reveals novel sites in HA protein that shift receptor binding preference of the H9N2 avian influenza virus 被引量:1
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作者 Yuncong Yin Wen Li +7 位作者 Rujian Chen Xiao Wang Yiting Chen Xinyuan Cui Xingbang Lu David M.Irwin Xuejuan Shen Yongyi Shen 《Virologica Sinica》 2025年第1期109-117,共9页
A switch from avian-typeα-2,3 to human-typeα-2,6 receptors is an essential element for the initiation of a pandemic from an avian influenza virus.Some H9N2 viruses exhibit a preference for binding to human-typeα-2,... A switch from avian-typeα-2,3 to human-typeα-2,6 receptors is an essential element for the initiation of a pandemic from an avian influenza virus.Some H9N2 viruses exhibit a preference for binding to human-typeα-2,6 receptors.This identifies their potential threat to public health.However,our understanding of the molecular basis for the switch of receptor preference is still limited.In this study,we employed the random forest algorithm to identify the potentially key amino acid sites within hemagglutinin(HA),which are associated with the receptor binding ability of H9N2 avian influenza virus(AIV).Subsequently,these sites were further verified by receptor binding assays.A total of 12 substitutions in the HA protein(N158D,N158S,A160 N,A160D,A160T,T163I,T163V,V190T,V190A,D193 N,D193G,and N231D)were predicted to prefer binding toα-2,6 receptors.Except for the V190T substitution,the other substitutions were demonstrated to display an affinity for preferential binding toα-2,6 receptors by receptor binding assays.Especially,the A160T substitution caused a significant upregulation of immune-response genes and an increased mortality rate in mice.Our findings provide novel insights into understanding the genetic basis of receptor preference of the H9N2 AIV. 展开更多
关键词 H9N2 Hemagglutinin(HA) Receptor binding preference Random forest algorithm Host shift Interspecies transmission
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Q-shift复小波的一种新型构造方法及其在图像去噪中的应用 被引量:3
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作者 王红霞 成礼智 吴翊 《信号处理》 CSCD 北大核心 2005年第5期520-524,543,共6页
为了提高复小波变换的效率,本文提出了一种设计Q-shift复小波滤波器的新方法。与目前采用多相位矩阵的晶格分解结构得到正交小波的方法不同的是,这里从更为一般的完全重构滤波器组出发寻求满足特定要求的正交小波。不但可以构造出系数... 为了提高复小波变换的效率,本文提出了一种设计Q-shift复小波滤波器的新方法。与目前采用多相位矩阵的晶格分解结构得到正交小波的方法不同的是,这里从更为一般的完全重构滤波器组出发寻求满足特定要求的正交小波。不但可以构造出系数更为简单、运算更加方便的小波,而且可以实现任意精度的复小波变换。该方法的可拓展性好,可以很方便的添加如高阶消失矩等限制并简化设计过程。以普遍采用的Q-shift10/10小波为例,利用本文构造的正交小波可将复小波变换中的乘法运算降低到原来的1/3,而加法基本相当,且小波的频率选择性质更好。将其用于图像去噪的实验表明,采用本文构造的小波可以显著提高处理速度并得到更高的峰值信噪比(PSNR)。 展开更多
关键词 复数小波 二分树复小波变换 Q—shift复小波变换 图像去噪 二进实小波变换 构造方法 复小波 完全重构滤波器组 shift 应用
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CAMSHIFT与基于核的目标跟踪算法的比较与分析 被引量:3
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作者 宁纪锋 姜光 吴成柯 《计算机工程与应用》 CSCD 北大核心 2009年第28期177-179,共3页
CAMSHIFT和基于核的目标跟踪是两种经典的基于Mean Shift的目标跟踪算法,它们的实现过程有许多类似之处。为了说明在实际应用中如何选择合理的跟踪方案,从目标模型、候选模型、核函数、迭代过程等方面对二者进行了深入的比较和分析,指... CAMSHIFT和基于核的目标跟踪是两种经典的基于Mean Shift的目标跟踪算法,它们的实现过程有许多类似之处。为了说明在实际应用中如何选择合理的跟踪方案,从目标模型、候选模型、核函数、迭代过程等方面对二者进行了深入的比较和分析,指出了二者的特点和区别,对于正确理解和使用这两种方法将会有一定的帮助。 展开更多
关键词 Mean shift 连续自适应均值移动跟踪算法(CAMshift) 基于核的目标跟踪 权值图像
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Chinese provincial-level new records for 96 resident bird species reveal poleward range shifts
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作者 Shengxi Chen Zhehao Chen +3 位作者 Hongtao Lin Haoting Duan Jiehua Yu Jiekun He 《Avian Research》 2025年第4期610-617,共8页
Anthropogenic climate change is altering species distributions globally.While species distributions are expected to shift to higher latitudes and elevations under global warming,empirical evidence on distribution shif... Anthropogenic climate change is altering species distributions globally.While species distributions are expected to shift to higher latitudes and elevations under global warming,empirical evidence on distribution shifts is mixed,and factors mediating the direction and magnitude of range shifts remain unclear.Using a dataset of 132new provincial records for 96 resident bird species from 2000 to 2023,we measured geographic distance,latitudinal shift,and temperature shift from each new record to the historical range for each species to test for poleward shifts.We assessed taxonomic variation in the magnitude of range shifts and used phylogenetic generalized linear mixed models to quantify relationships between species traits and the extent of range shifts.Our results revealed that new records occurred at a mean geographic distance of 420 km from historical ranges,with mean latitudinal shifts of+1.68°(poleward)and temperature shifts of-1.33℃(toward colder climates).The magnitude of geographic range shifts was strongly constrained by phylogenetic relatedness.Habitat breadth,habitat openness,and centroid latitude of historical ranges emerged as significant predictors of range shifts.Our results suggest that resident bird species'geographic ranges in China are shifting poleward,but the magnitude of these shifts is non-random across lineages.Species with broader habitat preferences and those from warmer climates are more likely to shift farther from their historical ranges and toward higher latitudes.This study emphasizes taxonomic variation in species range shifts and highlights the need for species-and site-specific conservation strategies under global warming. 展开更多
关键词 China Climate change Geographic distribution New records Phylogenetic analysis Range shifts
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Paradigm Shift:Construction of the “One-on- One” Teaching Model in Nursing Education for Neurology Nursing Students
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作者 Youxian Tan Yu Huang +1 位作者 Li Mo Xianying Tang 《Journal of Clinical and Nursing Research》 2025年第9期81-87,共7页
With the continuous improvement of the medical industry’s requirements for the professional capabilities of nursing talents,traditional nursing teaching models can hardly meet the needs of complex nursing work in neu... With the continuous improvement of the medical industry’s requirements for the professional capabilities of nursing talents,traditional nursing teaching models can hardly meet the needs of complex nursing work in neurology.This paper focuses on nursing education for neurology nursing students and explores the construction of the“one-on-one”teaching model,aiming to achieve a paradigm shift in nursing education.By analyzing the current status of neurology nursing education,this paper identifies the problems in traditional teaching models.Combining the advantages of the“one-on-one”teaching model,it elaborates on the construction path of this model from aspects such as the selection and training of teaching instructors,the design of teaching content,the innovation of teaching methods,and the improvement of the teaching evaluation system.The research shows that the“one-on-one”teaching model can significantly enhance nursing students’mastery of professional knowledge,clinical operation skills,communication skills,and emergency response capabilities,as well as strengthen their professional identity and sense of responsibility.It provides an effective way to cultivate high-quality nursing talents who can meet the needs of neurology nursing work and promotes the innovative development of nursing education. 展开更多
关键词 NEUROLOGY Nursing students One-on-one teaching model Nursing education Paradigm shift
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Unifying the Nepal height system and China height system based on gravity frequency shift approach
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作者 K.C.Shanker Ziyu Shen Wenbin Shen 《Geodesy and Geodynamics》 2025年第2期193-202,共10页
Highly accurate international height reference frames with long-term stability,global consistency,and homogeneity are crucial for monitoring sea level variations,understanding climate change,managing disasters,and sup... Highly accurate international height reference frames with long-term stability,global consistency,and homogeneity are crucial for monitoring sea level variations,understanding climate change,managing disasters,and supporting other applications that benefit scientific research and societal well-being.Currently,there are over 100 local height reference systems worldwide.Unifying these systems is a pivotal step toward constructing international height reference frames.The method introduced in this study-the gravity frequency shift via Satellite Frequency Signal Transfer(SFST)-represents a groundbreaking relativistic geodetic approach,demonstrating its potential to surpass the constraints of conventional techniques.The advent of high-precision optical atomic clocks(OAC)with an accuracy level of 1×10^(-18) has facilitated this method's implementation.The International Association of Geodesy(IAG)has established the International Height Reference System(IHRS)and its practical realization,the International Height Reference Frame(IHRF).Our study focuses on two neighbouring height systems:the China Height System(CHS)and the Nepal Height System(NHS),separated by the Himalayas and the Xizang plateau.We aim to unify these two systems by determining the geopotential and orthometric height differences between their respective height datum stations:the Qingdao Height Datum Station(QHDS)and the Madar Height Datum Station(MHDS)using a simulation experiment with the method mentioned above.Using an OAC with an accuracy of 1×10^(-18),we identified a geopotential difference of-8.348±0.464 m^(2)s^(-2) and an orthometric height difference of 0.786±0.047 m between QHDS and MHDS.These results suggest that the introduced method could unify any two height systems with fewcentimeter-level precision,emphasizing its significance in contributing to the construction of the IHRS/IHRF with today's required precision.In summary,the SFST technique is a novel geodetic method that offers an alternative for height system unification,delivering centimeter-level precision,surpassing traditional methods,and supporting the development of the IHRF. 展开更多
关键词 Vertical reference system Gravity frequency shift SFST IHRF Height system unification
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Isotope shifts due to the 1s^(2)2s^(2)S_(1/2)→1s^(2)2p^(2)P_(1/2,3/2)transitions of Li-like Th^(87)+ions
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作者 Huqiang Lu Bingbing Li +8 位作者 Mingye Yang Lin Dong Yanmin Wang Maijuan Li Lei Wu Jiguang Li Jun Jiang Chenzhong Dong Denghong Zhang 《Chinese Physics B》 2025年第7期290-295,共6页
The transition energies of the 1s^(2)2s^(2)S_(1/2)→1s^(2)2p^(2)p_(1/2,3/2)transitions in Li-like Th87+ions were calculated by combining the multi-configuration Dirac-Hartree-Fock(MCDHF)method with the model-quantum e... The transition energies of the 1s^(2)2s^(2)S_(1/2)→1s^(2)2p^(2)p_(1/2,3/2)transitions in Li-like Th87+ions were calculated by combining the multi-configuration Dirac-Hartree-Fock(MCDHF)method with the model-quantum electrodynamics(modelQED)approach.The effects of electron correlation,Breit interaction,and QED effects were analyzed in detail.The isotope shifts,including the mass shifts and field shifts,due to the 2s2S_(1/2)→2p^(2)P_(1/2,3/2)transitions were then calculated using two different methods,namely,the MCDHF method and the finite-field method.The results show that these two methods are in excellent agreement. 展开更多
关键词 isotope shift MCDHF method finite-field method QED effect
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The Blue Pivot China’s marine economy shifts from quantity to quality
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作者 Wang Yan 《China Report ASEAN》 2025年第11期18-21,共4页
According to the 2024 China Marine Economy Statistical Bulletin(hereinafter“the Bulletin”),China’s marine economy surpassed the 10 trillion yuan(US$1.38 trillion)mark for the first time in 2024,0.9 percentage point... According to the 2024 China Marine Economy Statistical Bulletin(hereinafter“the Bulletin”),China’s marine economy surpassed the 10 trillion yuan(US$1.38 trillion)mark for the first time in 2024,0.9 percentage points higher than the growth rate of the national GDP. 展开更多
关键词 growth rate marine economy national GDP trillion yuan quality shift
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Driving the Multipolar Shift G20 presidency of South Africa and other Global South countries indicates the emergence of‘key middle powers’
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作者 HUANG ZHONG SONG XIAOLI 《ChinAfrica》 2025年第11期22-24,共3页
Amid overlapping crises and uncertainties as the world enters an era of turbulence and transformation,the countries of the Global South are swiftly emerging from the periphery of world politics to the forefront of int... Amid overlapping crises and uncertainties as the world enters an era of turbulence and transformation,the countries of the Global South are swiftly emerging from the periphery of world politics to the forefront of international cooperation,playing an increasingly vital role in advancing humanity’s collective progress. 展开更多
关键词 South Africa Global South Turbulence Transformation multipolar shift Key middle powers UNCERTAINTIES G presidency
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