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“算”一词小补
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作者 宫领强 《电影评介》 2013年第8期111-112,共2页
对外汉语教材对"算"一词的英文翻译存在不等值情况,由此反观"算"的释义及性质确定问题。由"算"这个词我们应该注意下面两个方面的问题:一是应该注意对外汉语教材中的词汇及其英文标注之间的词性对应问题... 对外汉语教材对"算"一词的英文翻译存在不等值情况,由此反观"算"的释义及性质确定问题。由"算"这个词我们应该注意下面两个方面的问题:一是应该注意对外汉语教材中的词汇及其英文标注之间的词性对应问题;二是《现代汉语词典》在解词和确定词性时应该注意:(1)应该从具体的句义,甚至语段出发去归纳词义,句义或语段对词义具有制约和显化作用;(2)在确定同形但具有不同功能,以致具有不同词性的词时,应该在词典中凸显两者的使用条件。 展开更多
关键词 不等值 “算”
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关于北京大学藏秦简《算书乙种》的综合研究 被引量:1
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作者 邹大海 夏庆卓 《自然科学史研究》 CSSCI CSCD 北大核心 2024年第2期129-145,共17页
新近公布的北京大学藏秦简牍中有三种前所未知的数学著作,《算书乙种》是其中之一。本文首次对它进行系统的研究,分析其体例与编纂特点、知识类型与数学方法,以及相关的社会背景,并修正了以前学术界的若干不当认识。此书为撮编之作,结... 新近公布的北京大学藏秦简牍中有三种前所未知的数学著作,《算书乙种》是其中之一。本文首次对它进行系统的研究,分析其体例与编纂特点、知识类型与数学方法,以及相关的社会背景,并修正了以前学术界的若干不当认识。此书为撮编之作,结构上有一定层次,体现出编排的意图但考虑不周。作为实用算法式数学文献,此书不属于从“九数”发展至《九章算术》的经典系统,但它的内容仍为刘徽关于《九章算术》源于其先秦祖本的记载提供了新的直接证据。同时,此书也为研究秦国和秦代社会经济提供了难得的原始文献。 展开更多
关键词 北京大学藏秦简牍 书乙种》 《九章术》 中国数学史 计量制度 秦汉史
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《算法全能集》与元代社会经济初探
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作者 隋敬文 吕变庭 《自然科学史研究》 CSSCI CSCD 北大核心 2024年第3期295-306,共12页
《算法全能集》是一部元代数学专著,其记载的内容从侧面反映了元代社会经济问题,蕴藏着极高的史料价值。本文以《算法全能集》所载应用数学问题为基本史料,辅之以其他传统史料,对元代银钞流通、户等征配、物价波动等社会经济现象进行了... 《算法全能集》是一部元代数学专著,其记载的内容从侧面反映了元代社会经济问题,蕴藏着极高的史料价值。本文以《算法全能集》所载应用数学问题为基本史料,辅之以其他传统史料,对元代银钞流通、户等征配、物价波动等社会经济现象进行了考证。文章确认《算法全能集》成书于元代后半期,时间上早于《详明算法》和《丁巨算法》;书中官配实物问题体现了元代户等制“均平”的社会价值观念和“按比分配”、“递减分配”等几种现实执行途径;同时,《算法全能集》所载物价信息与现存史料基本吻合,较为真实地反映了当时社会经济的动态过程及江南平民的生活水平。以上分析,对丰富元代史料并深化元代社会经济研究有重要意义。 展开更多
关键词 元代 法全能集》 社会经济 经济数学 贾亨
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非句法结构“算了”的词汇化与语法化 被引量:42
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作者 刘红妮 《语言科学》 2007年第6期11-21,共11页
"算了"原本是非句法结构,"算"和"了"彼此之间不构成直接的句法关系。随着"算"词义的不断虚化,从"行"域到"知"域,加之常用于反问句中,非句法结构的"算了"开始表... "算了"原本是非句法结构,"算"和"了"彼此之间不构成直接的句法关系。随着"算"词义的不断虚化,从"行"域到"知"域,加之常用于反问句中,非句法结构的"算了"开始表示"不算了",从而词汇化为一个凝固的抽象义动词表示"作罢"之义,白话的"算了"逐渐替代文言的"罢了"。成词的"算了"发生语法化,进入到"言"域,成为语气助词,产生情态功能,并进一步语法化而产生话语标记功能。文章最后从现代汉语共时平面进行探讨,指出研究类似演变要注意的共性问题。 展开更多
关键词 “算了”非句法结构的词汇化 语法化 情态 话语标记
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“就算”的词汇化及其再演变研究 被引量:3
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作者 刘红妮 《汉语学习》 CSSCI 北大核心 2021年第4期3-12,共10页
本文从历时角度考察现代汉语连词“就算”的形成,探讨与“就算”有关的一系列演变。“就算”先是从短语词汇化为连词,词汇化之后并没有停止演变,而是进一步发生构式化,形成“就算X,也/但Y”等构式;此外,“就算”还进一步发生再词汇化,... 本文从历时角度考察现代汉语连词“就算”的形成,探讨与“就算”有关的一系列演变。“就算”先是从短语词汇化为连词,词汇化之后并没有停止演变,而是进一步发生构式化,形成“就算X,也/但Y”等构式;此外,“就算”还进一步发生再词汇化,形成新连词“就算是”。汉语有些词在词汇化之后,还会再发生进一步的相关演变。 展开更多
关键词 “就算” 词汇化 再演变 构式化 再词汇化
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双古堆汉简《算术书》校释及相关问题 被引量:1
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作者 周序林 《自然科学史研究》 CSSCI CSCD 北大核心 2023年第3期267-280,共14页
1977年安徽阜阳双古堆1号汉墓出土了一批简牍,其中有损坏严重的数学简,整理者共辑得30余枚残简,并据内容拟题为《算术书》,还释读了其中4枚残简简文。在前人基础上,本文首次对所有已刊布残简进行了释读,并重新编联。结果显示,仅有3组(枚... 1977年安徽阜阳双古堆1号汉墓出土了一批简牍,其中有损坏严重的数学简,整理者共辑得30余枚残简,并据内容拟题为《算术书》,还释读了其中4枚残简简文。在前人基础上,本文首次对所有已刊布残简进行了释读,并重新编联。结果显示,仅有3组(枚)残简简文文意相对清晰完整,即残简1、残简28+27+21+20+5、残简24+25。对比《九章算术》相关算题,确认它们分别与《九章算术》“均输”章第25题、第1题和“少广”章第8题相合。考察《九章算术》的删补者张苍与双古堆1号汉墓墓主的情况,认为二者有条件并有可能在算学方面有交流。双古堆汉简《算术书》与其他简牍算书有着不一样的血统,张苍在整理《九章算术》过程中形成的一个本子可能是它的一个重要来源。 展开更多
关键词 双古堆汉简 术书》 《九章术》 张苍
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Research on Euclidean Algorithm and Reection on Its Teaching
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作者 ZHANG Shaohua 《应用数学》 北大核心 2025年第1期308-310,共3页
In this paper,we prove that Euclid's algorithm,Bezout's equation and Divi-sion algorithm are equivalent to each other.Our result shows that Euclid has preliminarily established the theory of divisibility and t... In this paper,we prove that Euclid's algorithm,Bezout's equation and Divi-sion algorithm are equivalent to each other.Our result shows that Euclid has preliminarily established the theory of divisibility and the greatest common divisor.We further provided several suggestions for teaching. 展开更多
关键词 Euclid's algorithm Division algorithm Bezout's equation
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电力市场中计算输电电价的一种新方法 被引量:28
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作者 任震 吴国玥 黄雯莹 《中国电机工程学报》 EI CSCD 北大核心 2003年第1期37-40,170,共5页
该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合... 该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合理、完善。经IEEE6节点系统算例证明,该文所提的模型和算法是正确而有效的,具有重要的理论意义和工程实际价值,特别是对于在厂网分开后电网建设以及维护电网稳定的资金筹措有相当的指导价值。 展开更多
关键词 电网 无功功率 边际成本理论 潮流计 电力市场 输电电价
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Products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball
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作者 ZHANG Chao QIN Yuehai 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第2期160-169,共10页
The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic fu... The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic functions in the unit ball by radial derivative.Then we extend the Sharma's results. 展开更多
关键词 composition operator multiplication operator differentiation operator weighted Bergman space
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An Algorithm for Cloud-based Web Service Combination Optimization Through Plant Growth Simulation
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作者 Li Qiang Qin Huawei +1 位作者 Qiao Bingqin Wu Ruifang 《系统仿真学报》 北大核心 2025年第2期462-473,共12页
In order to improve the efficiency of cloud-based web services,an improved plant growth simulation algorithm scheduling model.This model first used mathematical methods to describe the relationships between cloud-base... In order to improve the efficiency of cloud-based web services,an improved plant growth simulation algorithm scheduling model.This model first used mathematical methods to describe the relationships between cloud-based web services and the constraints of system resources.Then,a light-induced plant growth simulation algorithm was established.The performance of the algorithm was compared through several plant types,and the best plant model was selected as the setting for the system.Experimental results show that when the number of test cloud-based web services reaches 2048,the model being 2.14 times faster than PSO,2.8 times faster than the ant colony algorithm,2.9 times faster than the bee colony algorithm,and a remarkable 8.38 times faster than the genetic algorithm. 展开更多
关键词 cloud-based service scheduling algorithm resource constraint load optimization cloud computing plant growth simulation algorithm
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Numerical Simulation of Microstructure Refinement of Al-Cu-Mg-Ag Alloy During Solidification
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作者 ZHU Shiqing ZHANG Hong CHEN Linghao 《材料科学与工程学报》 北大核心 2025年第4期513-519,524,共8页
Al-Cu-Mg-Ag alloys have become a research hotspot because of its good heat resistance.Its excellent mechanical properties are inseparable from the regulation of the structure by researchers.The method of material stru... Al-Cu-Mg-Ag alloys have become a research hotspot because of its good heat resistance.Its excellent mechanical properties are inseparable from the regulation of the structure by researchers.The method of material structure simulation has become more and more perfect.This study employs numerical simulation to investigate the microstructure evolution of Al-Cu-Mg-Ag alloys during solidification with the aim of controlling its structure.The size distribution of Ti-containing particles in an Al-Ti-B master alloy was characterized via microstructure observation,serving as a basis for optimizing the nucleation density parameters for particles of varying radii in the phase field model.The addition of refiner inhibited the growth of dendrites and no longer produced coarse dendrites.With the increase of refiner,the grains gradually tended to form cellular morphology.The refined grains were about 100μm in size.Experimental validation of the simulated as-cast grain morphology was conducted.The samples were observed by metallographic microscope and scanning electron microscope.The addition of refiner had a significant effect on the refinement of the alloy,and the average grain size after refinement was also about 100μm.At the same time,the XRD phase identification of the alloy was carried out.The observation of the microstructure morphology under the scanning electron microscope showed that the precipitated phase was mainly concentrated on the grain boundary.The Al_(2)Cu accounted for about 5%,and the matrix phase FCC accounted for about 95%,which also corresponded well with the simulation results. 展开更多
关键词 Al-Cu-Mg-Ag alloy Phase field simulation Dendrite refinement Phase diagram calculation
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Equilibrium Strategies in M/M/1 Retrial Queues with Variable Service Rate
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作者 LIU Yuanyuan YAN Zhaozeng YANG Qin 《应用概率统计》 北大核心 2025年第3期448-466,共19页
We consider a single server constant retrial queue,in which a state-dependent service policy is used to control the service rate.Customer arrival follows Poisson process,while service time and retrial time are exponen... We consider a single server constant retrial queue,in which a state-dependent service policy is used to control the service rate.Customer arrival follows Poisson process,while service time and retrial time are exponential distributions.Whenever the server is available,it admits the retrial customers into service based on a first-come first-served rule.The service rate adjusts in real-time based on the retrial queue length.An iterative algorithm is proposed to numerically solve the personal optimal problem in the fully observable scenario.Furthermore,we investigate the impact of parameters on the social optimal threshold.The effectiveness of the results is illustrated by two examples. 展开更多
关键词 variable service rate retrial queues real-time adaptability equilibrium strategies ALGORITHM
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Syntheses,crystal structures,and characterizations of two cadmium(Ⅱ)coordination polymers
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作者 LI Xiumei LI Linlin +1 位作者 LIU Bo PAN Yaru 《无机化学学报》 北大核心 2025年第3期613-623,共11页
Two new transition-metal coordination polymers,{[Cd(oba)(L)_(2)]·H_(2)O}_n(1)and[Cd(4-nph)(L)_(2)]_n(2)(H_(2)oba=4,4'-oxydibenzoic acid,4-H_(2)nph=4-nitrophthalic acid,L=2,2'-biimidazole),were successfull... Two new transition-metal coordination polymers,{[Cd(oba)(L)_(2)]·H_(2)O}_n(1)and[Cd(4-nph)(L)_(2)]_n(2)(H_(2)oba=4,4'-oxydibenzoic acid,4-H_(2)nph=4-nitrophthalic acid,L=2,2'-biimidazole),were successfully synthesized under hydrothermal conditions and characterized structurally by IR spectroscopy,elemental analyses,single-crystal X-ray diffraction,powder X-ray diffraction,and thermogravimetric analysis.The results of single-crystal X-ray diffraction show that complex 1 presents a 1D zigzag chain structure and further extends to a 2D network through N—H…O hydrogen bonds andπ-πstacking interactions.Meanwhile,complex 2 has a zero-dimensional structure and also extends to form a 2D network through N—H…O hydrogen bonds andπ-πstacking interactions.In addition,both 1and 2 exhibited luminescent properties in the solid state.Furthermore,quantum chemical calculations were carried out on the"molecular fragments"extracted from the crystal structures of 1 and 2 using the PBE0/LANL2DZ method constructed by the Gaussian 16 program.The calculated values signify a significant covalent interaction between the coordination atoms and the Cd(Ⅱ)ions.CCDC:2332173,1;2332176,2. 展开更多
关键词 coordination polymer cadmium(Ⅱ)complex crystal structure quantum⁃chemical calculations
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Some studies on stochastic optimization based quantitative risk management
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作者 HU Zhaolin 《运筹学学报(中英文)》 北大核心 2025年第3期135-159,共25页
Risk management often plays an important role in decision making un-der uncertainty.In quantitative risk management,assessing and optimizing risk metrics requires eficient computing techniques and reliable theoretical... Risk management often plays an important role in decision making un-der uncertainty.In quantitative risk management,assessing and optimizing risk metrics requires eficient computing techniques and reliable theoretical guarantees.In this pa-per,we introduce several topics on quantitative risk management and review some of the recent studies and advancements on the topics.We consider several risk metrics and study decision models that involve the metrics,with a main focus on the related com-puting techniques and theoretical properties.We show that stochastic optimization,as a powerful tool,can be leveraged to effectively address these problems. 展开更多
关键词 stochastic optimization quantitative risk management risk measure computing technique statistical property
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Solid-state Effects on Luminescence Properties of TADF Emitters Based on Pyrido[2,3-b]pyrazine-Dihydrophenazasilines Donor-acceptor Structures:Theoretical Study
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作者 LI Yuheng LIU Meiqi +2 位作者 HOU Baoming PAN Yuyu YANG Bing 《发光学报》 北大核心 2025年第2期354-365,共12页
Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular st... Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular structure and luminescence properties,TADF molecules are far from meeting the needs of practical applications in terms of variety and number.In this paper,three twisted TADF molecules are studied and their photophysical properties are theoretically predicted based on the thermal vibrational correlation function method combined with multiscale calculations.The results show that all the molecules exhibit fast reverse intersystem crossing(RISC)rates(kRISC),predicting their TADF luminescence properties.In addition,the binding of DHPAzSi as the donor unit with different acceptors can change the dihedral angle between the ground and excited states,and the planarity of the acceptors is positively correlated with the reorganization energy,a property that has a strong influence on the non-radiative process.Furthermore,a decrease in the energy of the molecular charge transfer state and an increase in the kRISC were observed in the films.This study not only provides a reliable explanation for the observed experimental results,but also offers valuable insights that can guide the design of future TADF molecules. 展开更多
关键词 solid-state effects thermally activated delayed fluorescence(TADF) theoretical study multi-scale simulation
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Electrocatalytic Nitric Oxide Reduction to Yield Ammonia over Fe_(3)C Nanocrystals
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作者 Sen Lin Lang Zhang +4 位作者 Tong Hou Jun-Yang Ding Zi-Mo Peng Yi-Fan Liu Xi-Jun Liu 《电化学(中英文)》 北大核心 2025年第4期1-11,共11页
Nitric oxide(NO),which generally originates from vehicle exhaust and industrial flue gases,is one of the most serious air pollutants.In this case,the electrochemical NO reduction reaction(NORR)not only removes the atm... Nitric oxide(NO),which generally originates from vehicle exhaust and industrial flue gases,is one of the most serious air pollutants.In this case,the electrochemical NO reduction reaction(NORR)not only removes the atmospheric pollutant NO but also produces valuable ammonia(NH_(3)).Hence,through the synthesis and modification of Fe_(3)C nanocrystal cata-lysts,the as-obtained optimal sample of Fe_(3)C/C-900 was adopted as the NORR catalyst at ambient conditions.As a result,the Fe_(3)C/C-900 catalyst showed an NH_(3)Faraday efficiency of 76.5%and an NH_(3)yield rate of 177.5μmol·h^(-1)·cm^(-2)at the working potentials of-0.8 and-1.2 V versus reversible hydrogen electrode(vs.RHE),respectively.And it delivered a stable NORR activity during the electrolysis.Moreover,we attribute the high NORR properties of Fe_(3)C/C-900 to two aspects:one is the enhanced intrinsic activity of Fe_(3)C nanocrystals,including the lowering of the energy barrier of rate-limiting step(*NOH→*N)and the inhibition of hydrogen evolution;on the other hand,the favorable dispersion of active components,the effective adsorption of gaseous NO,and the release of liquid NH_(3)products facilitated by the porous carbon substrate. 展开更多
关键词 Nitric oxide reduction NH3 synthesis Fe_(3)C nanocrystal ELECTROLYSIS Theoretical calculation
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2D Plain and 3D Needle-punched C/SiC Composites:Low-velocity Impact Damage Behavior and Failure Mechanism
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作者 LUAN Xingang HE Dianwei +1 位作者 TU Jianyong CHENG Laifei 《无机材料学报》 北大核心 2025年第2期205-214,I0004,共11页
Continuous carbon fiber reinforced silicon carbide(C/SiC)composites are often subjected to low-velocity impacts when utilized as structural materials for thermal protection.However,research on in-plane impact damage a... Continuous carbon fiber reinforced silicon carbide(C/SiC)composites are often subjected to low-velocity impacts when utilized as structural materials for thermal protection.However,research on in-plane impact damage and multiple impact damage of C/SiC composites is limited.To investigate the in-plane impact damage behavior of C/SiC composites,a drop-weight impact test method was developed for strip samples,and these results were subsequently compared with those of C/SiC composite plates.Results show that the in-plane impact behavior of C/SiC strip samples is similar to that of C/SiC composite plates.Variation of the impact load with displacement is characterized by three stages:a nearly linear stage,a severe load drop stage,and a rebound stage where displacement occurs after the impact energy exceeds its peak value.Impact damage behavior under single and multiple impacts on 2D plain and 3D needled C/SiC composites was investigated at different impact energies and durations.Crack propagation in C/SiC composites was studied by computerized tomography(CT)technique.In the 2D plain C/SiC composite,load propagation between layers is hindered during impact,leading to delamination and 90°fiber brittle fracture.The crack length perpendicular to the impact direction increases with impact energy increases,resulting in more serious 0°fiber fracture and a larger area of fiber loss.In the 3D needled C/SiC composite,load propagates between the layers during impact through the connection of needled fibers.The fibers continue to provide substantial structural support,with notable instances of fiber pull-off and debonding.Consequently,the impact resistance is superior to that of 2D plain C/SiC composite.When the 3D needled C/SiC composite undergoes two successive impacts of 1.5 J,the energy absorption efficiency of the second impact is significantly lower,accompanied by a smaller impact displacement.Moreover,the total energy absorption efficiency of these two impacts of 1.5 J is lower than that of a single 3.0 J impact. 展开更多
关键词 ceramic-matrix composite FRACTURE low-velocity impact computerized tomography analysis
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A New Technique for Constructing Higher-order Iterative Methods to Solve Nonlinear Systems
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作者 XIAO Xiaoyong 《应用数学》 北大核心 2025年第3期762-774,共13页
In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introduc... In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introducing only one additional evaluation of the function in each step.Furthermore,some new efficient methods with a higher-order of convergence are obtained by using only a single matrix inversion in each iteration.Analyses of convergence properties and computational efficiency of these new methods are made and testified by several numerical problems.By comparison,the new schemes are more efficient than the corresponding existing ones,particularly for large problem sizes. 展开更多
关键词 Systems of nonlinear equation Order of convergence Higher-order method Extended Newton iteration Computational efficiency
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Deformations and extensions of modified λ-differential Lie-Yamaguti algebras
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作者 TENG Wen PAN Yuewei 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第4期115-127,共13页
The modifiedλ-differential Lie-Yamaguti algebras are considered,in which a modifiedλ-differential Lie-Yamaguti algebra consisting of a Lie-Yamaguti algebra and a modifiedλ-differential operator.First we introduce t... The modifiedλ-differential Lie-Yamaguti algebras are considered,in which a modifiedλ-differential Lie-Yamaguti algebra consisting of a Lie-Yamaguti algebra and a modifiedλ-differential operator.First we introduce the representation of modifiedλ-differential Lie-Yamaguti algebras.Furthermore,we establish the cohomology of a modifiedλ-differential Lie-Yamaguti algebra with coefficients in a representation.Finally,we investigate the one-parameter formal deformations and Abelian extensions of modifiedλ-differential Lie-Yamaguti algebras using the second cohomology group. 展开更多
关键词 Lie-Yamaguti algebra modifiedλ-differential operator representation and cohomology one-parameter formal deformation Abelian extension
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Predicting Hepatocellular Carcinoma Using Brightness Change Curves Derived From Contrast-enhanced Ultrasound Images
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作者 CHEN Ying-Ying JIANG Shang-Lin +3 位作者 HUANG Liang-Hui ZENG Ya-Guang WANG Xue-Hua ZHENG Wei 《生物化学与生物物理进展》 北大核心 2025年第8期2163-2172,共10页
Objective Primary liver cancer,predominantly hepatocellular carcinoma(HCC),is a significant global health issue,ranking as the sixth most diagnosed cancer and the third leading cause of cancer-related mortality.Accura... Objective Primary liver cancer,predominantly hepatocellular carcinoma(HCC),is a significant global health issue,ranking as the sixth most diagnosed cancer and the third leading cause of cancer-related mortality.Accurate and early diagnosis of HCC is crucial for effective treatment,as HCC and non-HCC malignancies like intrahepatic cholangiocarcinoma(ICC)exhibit different prognoses and treatment responses.Traditional diagnostic methods,including liver biopsy and contrast-enhanced ultrasound(CEUS),face limitations in applicability and objectivity.The primary objective of this study was to develop an advanced,lightweighted classification network capable of distinguishing HCC from other non-HCC malignancies by leveraging the automatic analysis of brightness changes in CEUS images.The ultimate goal was to create a user-friendly and cost-efficient computer-aided diagnostic tool that could assist radiologists in making more accurate and efficient clinical decisions.Methods This retrospective study encompassed a total of 161 patients,comprising 131 diagnosed with HCC and 30 with non-HCC malignancies.To achieve accurate tumor detection,the YOLOX network was employed to identify the region of interest(ROI)on both B-mode ultrasound and CEUS images.A custom-developed algorithm was then utilized to extract brightness change curves from the tumor and adjacent liver parenchyma regions within the CEUS images.These curves provided critical data for the subsequent analysis and classification process.To analyze the extracted brightness change curves and classify the malignancies,we developed and compared several models.These included one-dimensional convolutional neural networks(1D-ResNet,1D-ConvNeXt,and 1D-CNN),as well as traditional machine-learning methods such as support vector machine(SVM),ensemble learning(EL),k-nearest neighbor(KNN),and decision tree(DT).The diagnostic performance of each method in distinguishing HCC from non-HCC malignancies was rigorously evaluated using four key metrics:area under the receiver operating characteristic(AUC),accuracy(ACC),sensitivity(SE),and specificity(SP).Results The evaluation of the machine-learning methods revealed AUC values of 0.70 for SVM,0.56 for ensemble learning,0.63 for KNN,and 0.72 for the decision tree.These results indicated moderate to fair performance in classifying the malignancies based on the brightness change curves.In contrast,the deep learning models demonstrated significantly higher AUCs,with 1D-ResNet achieving an AUC of 0.72,1D-ConvNeXt reaching 0.82,and 1D-CNN obtaining the highest AUC of 0.84.Moreover,under the five-fold cross-validation scheme,the 1D-CNN model outperformed other models in both accuracy and specificity.Specifically,it achieved accuracy improvements of 3.8%to 10.0%and specificity enhancements of 6.6%to 43.3%over competing approaches.The superior performance of the 1D-CNN model highlighted its potential as a powerful tool for accurate classification.Conclusion The 1D-CNN model proved to be the most effective in differentiating HCC from non-HCC malignancies,surpassing both traditional machine-learning methods and other deep learning models.This study successfully developed a user-friendly and cost-efficient computer-aided diagnostic solution that would significantly enhances radiologists’diagnostic capabilities.By improving the accuracy and efficiency of clinical decision-making,this tool has the potential to positively impact patient care and outcomes.Future work may focus on further refining the model and exploring its integration with multimodal ultrasound data to maximize its accuracy and applicability. 展开更多
关键词 computer-aided diagnostic deep learning hepatocellular carcinoma contrast-enhanced ultrasound brightness change curve
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