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基于互信息特征选择和递归特征消除的钢材疲劳强度预测
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作者 姚磊 黎振 +2 位作者 武川 孟亚飞 王孟超 《机械强度》 北大核心 2026年第1期72-78,共7页
【目的】为了解决疲劳强度预测中由于数据量不足和高维数据而引起的挑战,提出一种互信息特征选择和递归特征消除(Mutual Information Feature Selection and Recursive Feature Elimination,MIFS-RFE)相结合的方法。【方法】首先,采用M... 【目的】为了解决疲劳强度预测中由于数据量不足和高维数据而引起的挑战,提出一种互信息特征选择和递归特征消除(Mutual Information Feature Selection and Recursive Feature Elimination,MIFS-RFE)相结合的方法。【方法】首先,采用MIFS识别对模型预测最关键的特征。其次,在RFE阶段重点处理剩余特征,通过系统迭代过程选择最具信息量的特征,确保最终特征子集能够准确地支持疲劳强度预测。最后,将经过特征选择和消除处理得到的最终特征子集输入到随机森林回归(Random Forest Regression,RFR)、K最近邻回归(K Nearest Neighbor Regression,KNN)、支持向量回归(Support Vector Regression,SVR)和多层感知机(Multi-Layer Perceptron,MLP)模型中,综合分析各模型的预测性能。【结果】经过优化后,特征数据从原始的25维降到了13维。在测试过程中,RFR、KNN、SVR和MLP的决定系数R^(2)分别为0.9777、0.9725、0.9613和0.9766。相较于全部特征的测试结果,所提方法使得模型的R^(2)最大提升了0.0208。最后基于模型的Shapley加法解释(Shapley Additive Explanation,SHAP)值分析最优特征的影响性,验证了MIFS-RFE方法的有效性,说明所提方法在维持相对高性能的同时成功降低了特征维度,为疲劳强度预测提供了更有效的优化方案。 展开更多
关键词 疲劳强度 互信息特征选择 递归特征消除 机器学习 最优特征子集
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Diagonally loaded SMI algorithm based on inverse matrix recursion 被引量:7
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作者 Cao Jianshu Wang Xuegang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期160-163,共4页
The derivation of a diagonally loaded sample-matrix inversion (LSMI) algorithm on the busis of inverse matrix recursion (i.e.LSMI-IMR algorithm) is conducted by reconstructing the recursive formulation of covarian... The derivation of a diagonally loaded sample-matrix inversion (LSMI) algorithm on the busis of inverse matrix recursion (i.e.LSMI-IMR algorithm) is conducted by reconstructing the recursive formulation of covariance matrix. For the new algorithm, diagonal loading is by setting initial inverse matrix without any addition of computation. In addition, a corresponding improved recursive algorithm is presented, which is low computational complexity. This eliminates the complex multiplications of the scalar coefficient and updating matrix, resulting in significant computational savings. Simulations show that the LSMI-IMR algorithm is valid. 展开更多
关键词 Robust adaptive beamforming Space-time adaptive processing (STAP) Diagonal loading Inverse matrix recursion
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基于电碳分布特性的高速铁路四电系统碳排放因子测算方法
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作者 苏鹏飞 王果 +3 位作者 闵永智 郭文凯 陶金豆 李嘉祥 《铁道学报》 北大核心 2026年第1期76-87,共12页
为助力铁路行业实现碳达峰、碳中和目标,提出一种铁路四电系统运营期间系统级碳排放因子计算方法。通过设备级参数特征构建铁路四电系统拓扑结构,结合能源结构建立四电系统电碳耦合模型;考虑设备运营特性与碳排放特性建立能流-碳流递归... 为助力铁路行业实现碳达峰、碳中和目标,提出一种铁路四电系统运营期间系统级碳排放因子计算方法。通过设备级参数特征构建铁路四电系统拓扑结构,结合能源结构建立四电系统电碳耦合模型;考虑设备运营特性与碳排放特性建立能流-碳流递归追踪模型,系统刻画四电系统各设备之间的能流-碳流分布特征;基于能流-碳流递归追踪模型提出系统级动态综合碳排放因子计算方法。结果表明,牵引供电系统碳排放占比最高,其综合碳排放因子高达0.63086 kgCO_(2)/(kW·h),最大负荷时刻的电力间接碳排放量占总碳排放的87.88%。且由于直接碳排放的影响,通信、信号的碳排放因子相较于电力碳排放因子均有提升,电力系统的动态平均碳排放因子显著高于静态值。能流-碳流守恒性检查结果显示能流-碳流严格平衡,验证了本文方法的合理性与准确性。 展开更多
关键词 铁路运输 四电系统 电碳耦合 能流递归 碳流追踪 碳排放因子
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道路性能影响因素选择方法研究
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作者 李毅帆 王维庄 +3 位作者 丁小平 倪静哲 张利维 曹江 《山西建筑》 2026年第1期147-151,共5页
道路性能预测模型在道路养护与管理中发挥着至关重要的作用,然而道路监测数据中包含的影响因素复杂多样,数据规模大、维度高、质量参差不齐,并且影响因素之间存在复杂的非线性关系,评价道路性能影响因素的重要性有助于提高决策模型的有... 道路性能预测模型在道路养护与管理中发挥着至关重要的作用,然而道路监测数据中包含的影响因素复杂多样,数据规模大、维度高、质量参差不齐,并且影响因素之间存在复杂的非线性关系,评价道路性能影响因素的重要性有助于提高决策模型的有效性和可靠性。文中对递归特征消除法进行改进,将道路性能影响因素的筛选流程分成两个阶段:第一阶段基于Spearman系数和随机森林方法进行初筛;第二阶段基于递归消除法进行复筛。研究表明,基于改进递归特征消除法的道路性能影响因素选择方法,降低了模型迭代训练过程中的计算资源消耗,避免了冗余特征的干扰,能够更精确地量化各影响因素与道路性能之间的关联强度,为道路性能的评估提供了更可靠的分析工具。 展开更多
关键词 特征选择 Spearman系数 随机森林 递归特征消除 计算模型
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Fuzzy Shape Control Based on El man Dynamic Recursion Network Prediction Model 被引量:2
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作者 JIA Chun-yu LIU Hong-min 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2006年第1期31-35,共5页
In the strip rolling process, shape control system possesses the characteristics of nonlinearity, strong coupling, time delay and time variation. Based on self adapting Elman dynamic recursion network prediction model... In the strip rolling process, shape control system possesses the characteristics of nonlinearity, strong coupling, time delay and time variation. Based on self adapting Elman dynamic recursion network prediction model, the fuzzy control method was used to control the shape on four-high cold mill. The simulation results showed that the system can be applied to real time on line control of the shape. 展开更多
关键词 shape prediction shape control Elman dynamic recursion network parameter self-adjusting fuzzy control
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Nonlinear Program Construction and Verification Method Based on Partition Recursion and Morgan's Refinement Rules 被引量:2
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作者 WANG Changjing CAO Zhongxiong +3 位作者 YU Chuling WANG Changchang HUANG Qing ZUO Zhengkang 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2023年第3期246-256,共11页
The traditional program refinement strategy cannot be refined to an executable program,and there are issues such as low verification reliability and automation.To solve the above problems,this paper proposes a nonline... The traditional program refinement strategy cannot be refined to an executable program,and there are issues such as low verification reliability and automation.To solve the above problems,this paper proposes a nonlinear program construction and verification method based on partition recursion and Morgan’s refinement rules.First,we use recursive definition technique to characterize the initial specification.The specification is then transformed into GCL(Guarded Command Language)programs using loop invariant derivation and Morgan’s refinement rules.Furthermore,VCG(Verification Condition Generator)is used in the GCL program to generate the verification condition automatically.The Isabelle theorem prover then validates the GCL program’s correctness.Finally,the GCL code generates a C++executable program automatically via the conversion system.The effectiveness of this method is demonstrated using binary tree preorder traversal program construction and verification as an example.This method addresses the problem that the construction process’s loop invariant is difficult to obtain and the refinement process is insufficiently detailed.At the same time,the method improves verification process automation and reduces the manual verification workload. 展开更多
关键词 program construction partition recursion Morgan's refinement rules loop invariant VCG Isabelle theorem prover
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基于BIM真实构件库的装配式建筑立面模块化智能设计方法研究——以加拿大不列颠哥伦比亚大学Brock Commons学生公寓为例
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作者 罗佳宁 檀洋林 吴承灏雨 《华中建筑》 2026年第1期20-23,共4页
针对装配式建筑立面模块化设计,在后续建造执行层面,存在拆分设计结果与真实建造需求不匹配的问题,该文提出一种基于BIM真实构件库与递归算法的装配式建筑立面模块化智能设计方法。以加拿大Brock Commons学生公寓为例,通过对墙板构件进... 针对装配式建筑立面模块化设计,在后续建造执行层面,存在拆分设计结果与真实建造需求不匹配的问题,该文提出一种基于BIM真实构件库与递归算法的装配式建筑立面模块化智能设计方法。以加拿大Brock Commons学生公寓为例,通过对墙板构件进行系统集成视角下的拆解分析(建造类设计信息归纳)、BIM构件建造类参数信息的提炼定义、BIM构件建造类参数信息的重组拓展,建立多种标准化墙板组成的BIM真实构件库,继而结合递归算法、Dynamo和Python的协同应用,实现了一种从BIM真实构件库中挑选真实墙板逆向组合、并随机生成多种立面的模块化智能设计范式,为解决拆分设计结果与建造需求不匹配问题提供了新的思路。 展开更多
关键词 装配式建筑 BIM真实构件库 立面模块化 智能设计 递归算法
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THE RECURSION OPERATOR FOR A CONSTRAINED CKP HIERARCHY 被引量:2
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作者 李传忠 田可雷 +1 位作者 贺劲松 程艺 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1295-1302,共8页
This paper gives a recursion operator for a 1-constrained CKP hierarchy, and by the recursion operator it proves that the 1-constrained CKP hierarchy can be reduced to the mKdV hierarchy under condition q = r.
关键词 recursion operator constrained CKP hierarchy mKdV hierarchy
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GEE遥感特征混合优选提升高海拔树种分类精度
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作者 周赛 黄凯 +5 位作者 张加龙 王明星 滕晨凯 夏乐艳 姜新周 程滔 《北京林业大学学报》 北大核心 2026年第1期26-40,共15页
【目的】高海拔地区森林资源动态监测面临云雾干扰、训练样本匮乏及树种光谱相似性高等多重瓶颈,严重制约了优势树种空间分布的精准制图。本研究以香格里拉市典型纯林为对象,旨在利用多源遥感数据与多策略特征优选方法提升树种识别精度... 【目的】高海拔地区森林资源动态监测面临云雾干扰、训练样本匮乏及树种光谱相似性高等多重瓶颈,严重制约了优势树种空间分布的精准制图。本研究以香格里拉市典型纯林为对象,旨在利用多源遥感数据与多策略特征优选方法提升树种识别精度与模型泛化能力。【方法】研究基于GEE平台获取Sentinel-2光学时序、Sentinel-1雷达数据及SRTM地形数据,提取光谱、纹理、植被指数、雷达极化、地形及时序特征,构建基础特征集。采用随机森林(RF)模型确定特征优选前的最优方案后,并行J-M距离、ReliefF和RFE算法构建单一特征集,同时对这3种特征集进行并集融合构建并行混合特征集。将单一优选与并行混合特征集分别代入RF模型重新分类,对比优选前后方案确定最优分类方案。采用生产者精度(PA)、用户精度(UA)、调和平均值(F1)、总体精度(OA)和Kappa系数评价分类精度。【结果】(1)基于J-M距离、ReliefF和RFE并行混合的特征优选方案9精度最高(OA为94.82%,Kappa系数为0.94),优于特征优选前的最优方案5。(2)多源遥感数据协同分类效果优于单一数据源,仅使用Sentinel-2数据的OA为83.35%(Kappa系数0.79);依次引入Sentinel-1雷达特征、Sentinel-1的纹理特征、地形特征和Sentinel-2时序特征后,OA分别提升了0.87、6.28、8.08、10.18个百分点(Kappa系数分别为0.81、0.86、0.90、0.92),其中Sentinel-2时序特征的引入使分类精度提升了2.10个百分点。(3)植被指数时序曲线分析表明,优势树种在秋冬季节差异显著,可分离性强。【结论】基于GEE平台多源遥感数据协同J-M距离-ReliefF-RFE并行混合特征优选有效提升了香格里拉森林优势树种的识别精度,系统揭示了其空间分布格局,为高海拔地区森林资源的精准监测提供了技术支撑。 展开更多
关键词 树种分类 多源遥感数据 并行混合特征选择 Sentinel-2时序 Google Earth Engine(GEE) 随机森林(RF) 递归特征消除(RFE) J-M距离 香格里拉
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Foraging site recursion by forest elephants Elephas maximus borneensis 被引量:1
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作者 Megan ENGLISH Marc ANCRENAZ +3 位作者 Graeme GILLESPIE Benoit GOOSSENS Sen NATHAN Wayne LINKLATER 《Current Zoology》 SCIE CAS CSCD 2014年第4期551-559,共9页
Recursion by herbivores is the repeated use of the same site or plants. Recursion by wild animals is rarely investigated but may be ubiquitous. Optimal foraging theory predicts site recursion as a function of the qual... Recursion by herbivores is the repeated use of the same site or plants. Recursion by wild animals is rarely investigated but may be ubiquitous. Optimal foraging theory predicts site recursion as a function of the quality of the site, extent of its last use, and time since its last use because these influence site resource status and recovery. We used GPS collars, behaviour and site sampling to investigate recursion to foraging sites for two elephant Elephas maximus borneensis herds in the Lower Kinabatangan Wildlife Sanctuary, Borneo, over a 12 month period. Recursion occurred to 48 out of 87 foraging sites and was most common within 48 hours or between 151-250 days, indicating two different types ofrecursion. Recursion was more likely to occur if the site had previously been occupied for longer. Moreover, the time spent at a site at recursion was the same as the time spent at the site on the first occasion. The number of days that had passed between the first visit and recursion was also positively correlated with how much time was spent at the site at recursion. Habitat type also influenced the intensity of site-use, with more time spent at recursion within riverine/open grass areas along forest margins compared to other habitat types. Recursion is a common behaviour used by the elephants and its pattern suggests it may be a foraging strategy for revisiting areas of greater value. The qualities of recursion sites might usefully be incorporated into landscape management strategies for elephant conservation in the area [Current Zoology 60 (4): 551-559, 2014]. 展开更多
关键词 Asian elephant recursion Site re-use HERBIVORY Megaherbivore Optimal foraging
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On Recursion Operator of the q-KP Hierarchy 被引量:1
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作者 田可雷 朱晓鸣 贺劲松 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第9期263-268,共6页
It is the aim of the present article to give a general expression of flow equations of the q-KP hierarchy.The distinct difference between the q-KP hierarchy and the KP hierarchy is due to q-binomial and the action of ... It is the aim of the present article to give a general expression of flow equations of the q-KP hierarchy.The distinct difference between the q-KP hierarchy and the KP hierarchy is due to q-binomial and the action of q-shift operator θ, which originates from the Leibnitz rule of the quantum calculus. We further show that the n-reduction leads to a recursive scheme for these flow equations. The recursion operator for the flow equations of the q-KP hierarchy under the n-reduction is also derived. 展开更多
关键词 q-KP hierarchy flow equations recursion operator
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基于RFE-SHAP的具有可解释性纱线质量预测研究
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作者 张保威 郭智林 王永华 《棉纺织技术》 2026年第1期2-9,共8页
为优化纱线质量预测的特征选择过程,进一步消除小样本环境下存在的冗余特征,提高后续预测过程的准确性、可靠性,提出了一种基于结合递归特征消除算法(RFE)和SHAP的具有可解释性的纱线质量预测方法,即RFE⁃SHAP。首先,选择RFE作为迭代特... 为优化纱线质量预测的特征选择过程,进一步消除小样本环境下存在的冗余特征,提高后续预测过程的准确性、可靠性,提出了一种基于结合递归特征消除算法(RFE)和SHAP的具有可解释性的纱线质量预测方法,即RFE⁃SHAP。首先,选择RFE作为迭代特征选择方法,将支持向量回归(SVR)作为其评估器;然后,引入SHAP技术去量化原始特征对纱线强力及毛羽H值两种纱线质量指标的边际贡献值,从而辅助特征选择,进而提供更直观且解释性更强的特征选择策略;最后,结合神经网络构建纱线强力以及毛羽H值的预测模型。试验结果证明:经RFE⁃SHAP算法得到的最优特征子集作为纱线强力及毛羽H值预测模型的输入时,模型多个评价指标的效果均有提升,其中,对两种纱线质量指标预测的平均绝对百分比误差均未超过3%。认为:该方法具有较高的可行性,可以在一定程度上提高模型的预测性能。 展开更多
关键词 纱线质量预测 特征选择 递归特征消除算法 支持向量回归 SHAP技术
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Recursion Least Square Method to Study the Fault Diagnosis and Its Model of Hydraulic Equipment 被引量:2
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作者 Hu Guoqing Luo Renfei(Department of Mechanical and Electrical Engineering,Xiamen University, 361005, Xiamen, Fujian, P.R.ChinaEmail: gqhu@jingxian.xmu.edu.cn) 《International Journal of Plant Engineering and Management》 1999年第1期383-390,共8页
In this paper establishing model of the fault diagnosis of hydraulic equipment isdescribed in details. It also studies the advantage of the recursion least square method. When theLSM is used in compuring the fault of... In this paper establishing model of the fault diagnosis of hydraulic equipment isdescribed in details. It also studies the advantage of the recursion least square method. When theLSM is used in compuring the fault of hydraulic equipment, not only does it save the computerCPU-time and memory, but it also has a high computation speed and,makes it easy to identifythe estimation parameters. 展开更多
关键词 medel FAULT hydraulic equipment recursion least square method.
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用Recursion方法计算晶格声子谱
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作者 吴式玉 郑兆勃 《物理学报》 SCIE EI CAS 1983年第1期46-56,共11页
用Recursion方法计算了体心、面心、金刚石结构晶体的声子谱。计算结果表明了这种方法计算复杂晶格结构谱密度的有效性。 这一工作也为用Recursion方法处理复杂结构无序体系问题提供了准备。
关键词 声子谱 recursion 晶格结构 布里渊区 能带结构 矩阵元 无序体系
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Construction of AFLT States by Reflection Method and Recursion Formula
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作者 寿暴 吴剑锋 喻明 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第1期56-68,共13页
The AFLT states|PY1,Y2has reflection symmetry,Sn|PY1,Y2=|PY2,Y2,nb=2P,where S is the screening charge.AFLT state can be constructed using this reflect symmetry.We propose a recursion formula for this construction.The ... The AFLT states|PY1,Y2has reflection symmetry,Sn|PY1,Y2=|PY2,Y2,nb=2P,where S is the screening charge.AFLT state can be constructed using this reflect symmetry.We propose a recursion formula for this construction.The recursion formula is factorized completely. 展开更多
关键词 AGT duality AFLT states reflection method recursion formula
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Recursions in Calogero-Sutherland Model Based on Virasoro Singular Vectors
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作者 吴剑锋 续莺莺 喻明 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第5期743-758,共16页
The present work is much motivated by finding an explicit way in the construction of the Jack symmetric function,which is the spectrum generating function for the Calogero-Sutherland (CS) model.To accomplish this work... The present work is much motivated by finding an explicit way in the construction of the Jack symmetric function,which is the spectrum generating function for the Calogero-Sutherland (CS) model.To accomplish this work,the hidden Virasoro structure in the CS model is much explored.In particular,we found that the Virasoro singular vectors form a skew hierarchy in the CS model.Literally,skew is analogous to coset,but here specifically refer to the operation on the Young tableaux.In fact,based on the construction of the Virasoro singular vectors,this hierarchical structure can be used to give a complete construction of the CS states,i.e.the Jack symmetric functions,recursively.The construction is given both in operator formalism as well as in integral representation.This new integral representation for the Jack symmetric functions may shed some insights on the spectrum constructions for the other integrable systems. 展开更多
关键词 Calogero-Sutherland model Jack symmetric function recursion relations integral representation
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Optical recursional binormal optical visco Landau-Lifshitz electromagnetic optical density
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作者 Talat Körpinar Zeliha Körpinar 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第5期17-37,共21页
In this manuscript,we study a new version of the optical recursional binormal microbeam model for a flexible binormal microscale beam in terms of a binormal normalized operator.Also,we give new explanations for the op... In this manuscript,we study a new version of the optical recursional binormal microbeam model for a flexible binormal microscale beam in terms of a binormal normalized operator.Also,we give new explanations for the optical recursional visco Landau-Lifshitz binormal electromagnetic binormal microscale beam.Finally,we obtain an optical application for the normalized visco Landau-Lifshitz electromagnetic binormal optimistic density with an optical binormal resonator. 展开更多
关键词 optical recursion optical visco Landau-Lifshitz microscale flexible elastic microscale electromagnetic optimistic density visco microbeam model
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Construction of Recursion Formulas for Lax Pairs of (2+1)-Dimensional Equation: Modified Generalized Dispersive Long Wave Equation
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作者 TIANYong-Bo CHENGYi SHAONan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期807-812,共6页
In this article, we study the Lax pairs of -dimensional equation: the modified generalized dispersive long wave (MGDLW) equation. Based on the well-known binary Darboux transformation, we dig out the recursion formula... In this article, we study the Lax pairs of -dimensional equation: the modified generalized dispersive long wave (MGDLW) equation. Based on the well-known binary Darboux transformation, we dig out the recursion formulas of the first part of the Lax pairs. Then by further discussion and doing some revisional work, we make the recursion formulas fit for the second part of Lax pairs. At last, some solutions to the MGDLW equation are worked out by using the recursion formula. 展开更多
关键词 Lax pairs modified generalized dispersive long wave equation recursion formula SOLUTIONS
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Recursion-transform approach to compute the resistance of a resistor network with an arbitrary boundary 被引量:22
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作者 谭志中 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第2期94-100,共7页
We consider a profound problem of two-point resistance in the resistor network with a null resistor edge and an arbitrary boundary,which has not been solved before because the Green's function technique and the Lapla... We consider a profound problem of two-point resistance in the resistor network with a null resistor edge and an arbitrary boundary,which has not been solved before because the Green's function technique and the Laplacian matrix approach are invalid in this case.Looking for the exact solutions of resistance is important but difficult in the case of the arbitrary boundary since the boundary is a wall or trap which affects the behavior of a finite network.In this paper,we give a general resistance formula that is composed of a single summation by using the recursion-transform method.Meanwhile,several interesting results are derived by the general formula.Further,the current distribution is given explicitly as a byproduct of the method. 展开更多
关键词 exact solution resistor network matrix equation recursion-transform boundary conditions
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NONLOCAL SYMMETRIES AND NONLOCAL RECURSION OPERATORS
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作者 陈玉福 张鸿庆 《Acta Mathematica Scientia》 SCIE CSCD 2001年第1期103-108,共6页
An expose about covering method on differential equations was given. The general formulae to determine nonlocal symmetries were derived which are analogous to the prolongation formulae of generalized symmetries. In ad... An expose about covering method on differential equations was given. The general formulae to determine nonlocal symmetries were derived which are analogous to the prolongation formulae of generalized symmetries. In addition., a new definition of nonlocal recursion operators was proposed, which gave a satisfactory explaination in covering theory for the integro-differential recursion operators. 展开更多
关键词 differential equations nonlocal symmetries recursion operators
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