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Multi-Order Neighborhood Fusion Based Multi-View Deep Subspace Clustering
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作者 Kai Zhou Yanan Bai +1 位作者 Yongli Hu Boyue Wang 《Computers, Materials & Continua》 2025年第3期3873-3890,共18页
Existing multi-view deep subspace clustering methods aim to learn a unified representation from multi-view data,while the learned representation is difficult to maintain the underlying structure hidden in the origin s... Existing multi-view deep subspace clustering methods aim to learn a unified representation from multi-view data,while the learned representation is difficult to maintain the underlying structure hidden in the origin samples,especially the high-order neighbor relationship between samples.To overcome the above challenges,this paper proposes a novel multi-order neighborhood fusion based multi-view deep subspace clustering model.We creatively integrate the multi-order proximity graph structures of different views into the self-expressive layer by a multi-order neighborhood fusion module.By this design,the multi-order Laplacian matrix supervises the learning of the view-consistent self-representation affinity matrix;then,we can obtain an optimal global affinity matrix where each connected node belongs to one cluster.In addition,the discriminative constraint between views is designed to further improve the clustering performance.A range of experiments on six public datasets demonstrates that the method performs better than other advanced multi-view clustering methods.The code is available at https://github.com/songzuolong/MNF-MDSC(accessed on 25 December 2024). 展开更多
关键词 Multi-view subspace clustering subspace clustering deep clustering multi-order graph structure
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Solving a Nonlinear Multi-Order Fractional Differential Equation Using Legendre Pseudo-Spectral Method
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作者 Yin Yang 《Applied Mathematics》 2013年第1期113-118,共6页
In this paper, we apply the Legendre spectral-collocation method to obtain approximate solutions of nonlinear multi-order fractional differential equations (M-FDEs). The fractional derivative is described in the Caput... In this paper, we apply the Legendre spectral-collocation method to obtain approximate solutions of nonlinear multi-order fractional differential equations (M-FDEs). The fractional derivative is described in the Caputo sense. The study is conducted through illustrative example to demonstrate the validity and applicability of the presented method. The results reveal that the proposed method is very effective and simple. Moreover, only a small number of shifted Legendre polynomials are needed to obtain a satisfactory result. 展开更多
关键词 LEGENDRE Pseudo-Spectral Method multi-order FRACTIONAL DIFFERENTIAL EQUATIONS Caputo DERIVATIVE
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一类分数阶抛物型PDE-ODE级联系统的输出反馈镇定
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作者 李霞 张传佳 孔臣臣 《曲阜师范大学学报(自然科学版)》 2026年第1期19-33,共15页
研究了一类分数阶抛物型PDE-ODE级联系统的输出反馈镇定问题.与相关文献不同的是,所研究系统的PDE和ODE子系统均是分数阶的,其中PDE子系统是n维的(不再是一维的),且仅ODE子系统部分状态和PDE子系统一个边界信息可量测.这增加了控制方法... 研究了一类分数阶抛物型PDE-ODE级联系统的输出反馈镇定问题.与相关文献不同的是,所研究系统的PDE和ODE子系统均是分数阶的,其中PDE子系统是n维的(不再是一维的),且仅ODE子系统部分状态和PDE子系统一个边界信息可量测.这增加了控制方法的适用范围,同时也增大了控制设计和稳定性分析的难度.为此,首先通过无穷维反推方法构造状态观测器以估计系统的不可测状态.然后,利用无穷维反推方法设计输出反馈控制器以确保闭环系统在一定范数意义下是Mittag-Leffer稳定的.最后,通过数值仿真验证了所提理论方法的有效性. 展开更多
关键词 分数阶PDE-odE级联系统 镇定 输出反馈 无穷维反推方法
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地铁客流不均衡分布现状下运营优化研究——从OD客流预测及现实管理应用角度分析
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作者 邓婉仪 张海杰 《交通企业管理》 2026年第1期57-59,共3页
地铁OD客流能够反映客流在地铁系统内的流向,能够为现实的车组应用等需求提供数据支撑。然而,在现实情况中,客流在不同时刻与不同区段呈现出显著的离散性与不均衡性分布,完全依靠历史客流数据无法准确把握未来一段时间的客流水平。对OD... 地铁OD客流能够反映客流在地铁系统内的流向,能够为现实的车组应用等需求提供数据支撑。然而,在现实情况中,客流在不同时刻与不同区段呈现出显著的离散性与不均衡性分布,完全依靠历史客流数据无法准确把握未来一段时间的客流水平。对OD客流进行预测研究,并对其在现实运营管理中的应用进行分析探讨,对于地铁公司的日常管理运营具有现实意义。 展开更多
关键词 地铁 od客流 不均衡分布 预测研究 运营管理应用
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ODES理念和“4R”标准——多尔后现代课程观的一种解读及其对我国新课程改革的启示 被引量:5
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作者 曾令泰 肖美艳 《湖南工程学院学报(社会科学版)》 2005年第3期92-94,共3页
伴随着美国后现代运动的兴起而出现的课程理论革新是对美国现代主义课程理论一次深刻的革命。多尔是后现代课程观的集大成者。论述了多尔的后现代课程观提出的时代背景,并对其后现代课程观的建构基础———开放、对话、体验、自组织理... 伴随着美国后现代运动的兴起而出现的课程理论革新是对美国现代主义课程理论一次深刻的革命。多尔是后现代课程观的集大成者。论述了多尔的后现代课程观提出的时代背景,并对其后现代课程观的建构基础———开放、对话、体验、自组织理念和“4R”标准进行了解读,最后揭示了其对我国现阶段新课程改革的意义。 展开更多
关键词 odes 4R 多尔 后现代课程观 启示
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固定OD路径分配下的路网通行能力信号优化模型
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作者 卢凯 周凌霄 +2 位作者 张晓春 何淑霖 林科 《东南大学学报(自然科学版)》 北大核心 2025年第2期544-552,共9页
为测算与优化路网通行能力,针对断面、路段、路网3个层级,根据交叉口信号相位结构与配时参数,分别给出各层级通行能力的计算方法。通过建立路网通行能力优化模型与信号交叉口总延误优化模型,在保证路网通行能力最大的基础上,实现路网信... 为测算与优化路网通行能力,针对断面、路段、路网3个层级,根据交叉口信号相位结构与配时参数,分别给出各层级通行能力的计算方法。通过建立路网通行能力优化模型与信号交叉口总延误优化模型,在保证路网通行能力最大的基础上,实现路网信号交叉口总延误最小化,以兼顾路网通行能力与运行效率整体最优。案例仿真结果表明,所提模型能够较为准确地计算路网通行能力,模型计算结果与仿真实验数据偏差为1.60%。与Synchro优化方案相比,所提模型优化方案可使路网通行能力提高5.11%,车均延误时间减少12.28%,车均停车次数下降19.10%,取得了较为明显的优化效果。 展开更多
关键词 交通工程 城市路网 通行能力 od流量 信号优化 延误
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基于收费数据的高速公路改扩建路段OD反推方法
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作者 闫晟煜 赵转转 +3 位作者 赵凌煜 余娜 郑鑫 刘杨 《长安大学学报(自然科学版)》 北大核心 2025年第5期163-171,共9页
为应对新时期大规模高速公路改扩建规划需求,基于收费数据,提出了一种改扩建路段OD反推方法;考虑路段节点类型,提出了OD交通小区划分原则;梳理了改扩建路段OD反推流程,提出了域内型、途经型、到达型和发送型4种OD划分方法;针对途经型OD... 为应对新时期大规模高速公路改扩建规划需求,基于收费数据,提出了一种改扩建路段OD反推方法;考虑路段节点类型,提出了OD交通小区划分原则;梳理了改扩建路段OD反推流程,提出了域内型、途经型、到达型和发送型4种OD划分方法;针对途经型OD的复杂性,提出了途经型初始OD生成方法;分析了不加约束条件的反推解集,建立了基于最大熵原理的OD反推模型,采用拉格朗日乘数法求解模型,采用容量限制分配法实现了交通分配;运用TransCAD和Python对途经型OD进行加载与迭代,通过设定收敛误差控制离散统计量和最大上下行偏差率;以二广高速公路改扩建规划为例,验证了模型的可行性和运行效率,并分析了迭代次数与最大上下行偏差率的关系。研究结果表明:迭代次数增加时最大上下行偏差率减小,分步实施4次交通分配可实现路段交通量有效加载,迭代29次后离散统计量和最大上下行偏差率小于5%,迭代时间为5 min,离散统计量为1.32%,说明提出的路段OD反推模型能够有效且快速地完成实例路段的OD迭代与分配过程;由路段拓扑结构的8个枢纽可知,有2个枢纽的转向交通量超过了10000 pcu·d^(-1)的设计标准,需要设置双幅车道。综上所述,研究成果可支撑改扩建路段的规划与设计。 展开更多
关键词 交通工程 高速公路 改扩建规划 出行od 最大熵模型 收费数据
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聚变增殖包层用低活化9Cr-ODS钢的室温低周疲劳行为 被引量:1
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作者 王旗涛 李艳芬 +5 位作者 张家榕 李尧志 付海阳 李新乐 严伟 单以银 《金属学报》 北大核心 2025年第2期323-335,共13页
在现有研究中,低活化9Cr-ODS钢虽然具有优异的高温性能,但其低周疲劳性能及微观组织演变规律尚未全面揭示,本工作旨在揭示其在不同应变幅下的循环响应和裂纹扩展特性。采用应变控制测试方法,研究了低活化9Cr-ODS钢在0.3%~0.8%应变幅范... 在现有研究中,低活化9Cr-ODS钢虽然具有优异的高温性能,但其低周疲劳性能及微观组织演变规律尚未全面揭示,本工作旨在揭示其在不同应变幅下的循环响应和裂纹扩展特性。采用应变控制测试方法,研究了低活化9Cr-ODS钢在0.3%~0.8%应变幅范围内的室温低周疲劳性能,包括循环应力响应曲线、滞后回线、应变幅与寿命以及应力幅与塑性应变的关系,给出了相应的疲劳参数,并分析了疲劳过程中微观组织演变、疲劳断口形貌及裂纹扩展特性等。结果表明,9Cr-ODS钢的循环应力响应行为与应变幅有关。随应变幅增加,材料的峰值拉应力增加,疲劳寿命降低,循环应变-寿命满足Coffin-Manson关系。9Cr-ODS钢在所有应变幅下未出现明显的循环硬化,但在0.5%~0.8%较高应变幅范围内发生了一定的循环软化。微观组织分析表明,随循环应变幅增加,亚结构发生了回复,位错密度降低,平均晶粒尺寸及大角度晶界占比逐渐增加,从而导致9Cr-ODS钢的循环软化。疲劳裂纹起源于样品表面,但裂纹源附近均未发现明显的夹杂物或析出相。裂纹以穿晶方式扩展,9Cr-ODS钢细的原始奥氏体晶界及亚晶界对裂纹扩展具有强烈的抑制作用。此外,在相同低应变幅且不降低循环疲劳寿命条件下,9Cr-ODS钢所能承受的峰值拉应力达到低活化铁素体/马氏体钢的2倍,显示出较优越的低周疲劳强度。 展开更多
关键词 odS钢 低周疲劳 疲劳寿命 微观组织 断裂特征
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Rising Acceptance of Life and Negative Capability—A Reading of John Keats's Odes 被引量:1
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作者 谢春燕 《海外英语》 2013年第5X期210-211,228,共3页
"Beauty is truth, truth beauty"-the famous line in English romantic poet John Keats'Ode on a Grecian Urn-has triggered wide discussion and numerous interpretations. From the point of"negative capabi... "Beauty is truth, truth beauty"-the famous line in English romantic poet John Keats'Ode on a Grecian Urn-has triggered wide discussion and numerous interpretations. From the point of"negative capability", a phrase first coined by Keats himself, this paper is attempting to display the consistency between that poetic line and the poet's creation and life attitude on the whole. For this purpose, this paper will mainly introduce and interpret five of Keats'famous odes in the order of their display of his"rising acceptance of life": Ode to a Nightingale, Ode on a Grecian Urn, Ode to Autumn, Ode on Melancholy and Ode on Indolence. This paper would like to show in the first three Keats's positive quest in different aspects and on certain levels, the fourth the underlying tone of life's polyphonous song, and the final the"negative capability"that constitutes his healthy attitude toward creation and life. Finally, this paper hopes to demonstrate that it is such capability that enables the poet to growingly accept life, and it is also essential to him as a philosophical poet. 展开更多
关键词 NEGATIVE capability KEATS odes
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关于死海地区臭氧耗损现象(ODEs)的研究综述
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作者 谷怿宸 曹乐 《环境化学》 CAS CSCD 北大核心 2022年第1期144-159,共16页
自1997年在死海地区的大气边界层中观测到午间臭氧浓度迅速下降的现象后,研究学者们即对该地区的臭氧耗损现象(ozone depletion events,简称ODEs)展开了研究。而在此之前,大气边界层内的ODEs现象普遍被认为只会发生在极地地区的特殊大... 自1997年在死海地区的大气边界层中观测到午间臭氧浓度迅速下降的现象后,研究学者们即对该地区的臭氧耗损现象(ozone depletion events,简称ODEs)展开了研究。而在此之前,大气边界层内的ODEs现象普遍被认为只会发生在极地地区的特殊大气现象。本文综述了关于死海地区ODEs研究的发展历史,主要展示了促使死海ODEs形成的物理化学机理、关于死海地区ODEs的观测和模拟研究,以及死海地区臭氧耗损现象的特点。与极地ODEs类似,造成死海地区的ODEs过程中臭氧耗损的主要化学物质是活性溴化物如氧化溴(BrO)等。但由于死海地区特殊的环境条件,该地区的ODEs在时间尺度上和空间尺度上与极地ODEs存在明显的差异。目前关于死海ODEs的观测研究主要以地面观测为主,并显示相较冬季,死海夏季ODEs的发生频率更高,臭氧耗损也更为明显。而目前关于死海ODEs的模拟研究则以零维和一维模拟为主,模拟中证实了臭氧和BrO之间的负相关关系,并揭示出非均相反应(溴爆炸机制和BrONO_(2)的水解)对于ODEs的重要影响。另外,模拟中还指出了氮氧化物对于ODEs的两面性作用,以及气象条件(如逆温层)对于ODEs产生的影响。现有研究还发现,死海地区特殊的地形、环境条件及其海水中的高溴含量都是促使当地产生ODEs的关键因素。死海ODEs的发生不仅会改变该地区大气边界层中成分(例如汞)的浓度和寿命,也会影响大气的氧化能力,而这些都会对该地区人类的生活和健康产生潜在的作用,因此有必要加深对于该现象的总体认识。 展开更多
关键词 臭氧 odes 死海地区 卤素 氮氧化物
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How to Make Systems of Nonlinear Autonomous ODEs with Attractor-Behavior, by First Making the General Solutions: Part One 被引量:1
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作者 Magne Stensland 《Journal of Applied Mathematics and Physics》 2022年第12期3814-3835,共22页
In this paper, we will present a new method for making first-order systems of nonlinear autonomous ODEs that exhibit limit cycles with a specific geometric shape in two and three dimensions, or systems of ODEs where s... In this paper, we will present a new method for making first-order systems of nonlinear autonomous ODEs that exhibit limit cycles with a specific geometric shape in two and three dimensions, or systems of ODEs where surfaces in three dimensions have attractor behavior. The method is to make the general solutions first by using the exponential function, sine and cosine. We are building up the general solutions bit for bit according to the constant terms that contain the formula of the desired limit cycle, and differentiating them. We will obtain a system of ODEs with the desired behavior. We design the general solutions for a distinct purpose. Using the methods described in this paper, it is possible to make some systems of nonlinear ODEs that are exhibiting limit cycles with a distinct geometric shape in two or three dimensions, and some surfaces having attractor behavior. The pictures show the result. 展开更多
关键词 System of Nonlinear odes Limit Cycle General Solution ATTRACTOR
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含Zr ODS FeCrAl合金在550℃Pb-Bi熔液中的腐蚀行为
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作者 张晓晨 李静 +2 位作者 李长记 熊良银 刘实 《金属学报》 北大核心 2025年第9期1320-1334,共15页
结构材料与液态Pb-Bi熔液的相容性是铅冷快堆发展应用亟待解决的关键问题,氧化物弥散强化(ODS)FeCrAl合金是极具发展潜力的结构材料之一,但是对于高强度的含Zr ODS FeCrAl合金在液态Pb-Bi熔液中的研究较少。本工作利用SEM、XRD、EPMA等... 结构材料与液态Pb-Bi熔液的相容性是铅冷快堆发展应用亟待解决的关键问题,氧化物弥散强化(ODS)FeCrAl合金是极具发展潜力的结构材料之一,但是对于高强度的含Zr ODS FeCrAl合金在液态Pb-Bi熔液中的研究较少。本工作利用SEM、XRD、EPMA等分析技术研究了粉末冶金法制备的含Zr ODS FeCrAl合金经550℃饱和氧液态Pb-Bi共晶合金浸泡10000 h后的腐蚀产物,研究了Zr、Ti、Al和O等元素含量对ODS FeCrAl合金耐Pb-Bi腐蚀性能的影响。结果表明,由于Zr元素在氧化初期抑制Al与O元素结合、阻碍Al元素向外扩散,使得含Zr ODS FeCrAl合金表面无法生成连续、保护性的Al_(2)O_(3)薄膜,腐蚀产物主要由薄的Al_(2)O_(3)膜和疖状的Fe的多层氧化物组成。疖状氧化物的分布和形貌受含Zr ODS FeCrAl合金中Ti、Al和O含量的影响。增加含Zr ODS FeCrAl合金中的O含量,会使Y-Zr-O纳米强化相高密度析出,基体中对Al_(2)O_(3)薄膜有不利影响的Zr含量降低,进而使疖状氧化物的数量、厚度及表面横向尺寸降低。在ODS FeCrAl合金中添加Ti元素,其对合金腐蚀行为的影响类似于Zr元素,可促进合金表面疖状氧化物数量增加。(4.0%~5.5%)Al的添加不能阻止含Zr ODS FeCrAl合金表面上生成Fe的氧化产物。 展开更多
关键词 含Zr odS FeCrAl合金 Pb-Bi腐蚀 Ti添加 O含量 AL含量
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聚变用低活化9Cr-ODS钢在高温高压水中的腐蚀行为及机理
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作者 付海阳 张家榕 +5 位作者 李尧志 王旗涛 李新乐 严伟 单以银 李艳芬 《金属学报》 北大核心 2025年第9期1305-1319,共15页
为了探究低活化9Cr氧化物弥散(9Cr-ODS)钢在设计服役环境下的氧化行为及机理,通过模拟聚变堆高温高压循环水腐蚀实验,研究了其在聚变堆设计冷却水中的腐蚀行为,并与中国低活化马氏体(CLAM)钢进行对比,阐释了腐蚀过程中表面及截面微观结... 为了探究低活化9Cr氧化物弥散(9Cr-ODS)钢在设计服役环境下的氧化行为及机理,通过模拟聚变堆高温高压循环水腐蚀实验,研究了其在聚变堆设计冷却水中的腐蚀行为,并与中国低活化马氏体(CLAM)钢进行对比,阐释了腐蚀过程中表面及截面微观结构的演化和氧化产物的形成与转变过程。结果表明,在325℃、15.5 MPa的静态高温高压水和动态高温高压水(温度25℃、压力15.5 MPa、流速5 mL/min)中,9Cr-ODS钢的腐蚀增重和氧化膜厚度均比CLAM钢低。在静态水中腐蚀时,2种材料的腐蚀产物均为外层为颗粒状的Fe_(3)O_(4)、内层为连续的富Cr、Fe的尖晶石的双层结构;随腐蚀时间从200 h增加至1000 h,氧化物颗粒尺寸和氧化膜厚度逐渐增加;然而在动态水中,2种钢的腐蚀增重及氧化膜厚度反而降低,其中CLAM钢外层氧化物的种类保持不变,但9Cr-ODS钢中除Fe_(3)O_(4)外还有少量Fe_(2)O_(3)生成。在相同腐蚀条件下,弥散的纳米氧化物、细化的晶粒以及较高的基体O含量对ODS钢耐腐蚀性能产生了积极作用,促进了保护性氧化膜内层的形成,同时也降低了腐蚀增重速率,使得9Cr-ODS钢具有比CLAM钢更优异的耐腐蚀性能。 展开更多
关键词 低活化odS钢 高温高压水 腐蚀 氧化膜
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Second Kind Shifted Chebyshev Polynomials for Solving the Model Nonlinear ODEs
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作者 Amr M. S. Mahdy N. A. H. Mukhtar 《American Journal of Computational Mathematics》 2017年第4期391-401,共11页
In this paper, we build the integral collocation method by using the second shifted Chebyshev polynomials. The numerical method solving the model non-linear such as Riccati differential equation, Logistic differential... In this paper, we build the integral collocation method by using the second shifted Chebyshev polynomials. The numerical method solving the model non-linear such as Riccati differential equation, Logistic differential equation and Multi-order ODEs. The properties of shifted Chebyshev polynomials of the second kind are presented. The finite difference method is used to solve this system of equations. Several numerical examples are provided to confirm the reliability and effectiveness of the proposed method. 展开更多
关键词 CHEBYSHEV Spectral Method RICCATI DIFFERENTIAL EQUATION Logistic DIFFERENTIAL EQUATION multi-order odes
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Combination Method for Parallel Computation in ODEs
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作者 Song Xiaoqiu(Beijing Institute of Computer Application and Simulation Technology ) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1996年第4期19-26,共8页
In this paper, a 3rd order combination method with three processes and a 4th order combination method with five processes for solving ODEs are discussed. These methods are the Runge-Kutta method combined with a linear... In this paper, a 3rd order combination method with three processes and a 4th order combination method with five processes for solving ODEs are discussed. These methods are the Runge-Kutta method combined with a linear multistep method, which overcomes the defect of the 3rd order parallel Runge-Kutta method discussed in [1]. 展开更多
关键词 SOFTWARE RELIABILITY Numerical analysis Combination method Parallel Computation odes.
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An Attempt to Make Non-Elementary Functions That Are Giving Solutions to Some Second-Order Nonlinear Autonomous ODEs 被引量:2
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作者 Magne Stensland 《Journal of Applied Mathematics and Physics》 2022年第1期56-67,共12页
In this paper, we define an exponential function whose exponent is the product of a real number and the upper limit of integration in a non-elementary integral that can be arbitrary. We are using Abel’s methods, desc... In this paper, we define an exponential function whose exponent is the product of a real number and the upper limit of integration in a non-elementary integral that can be arbitrary. We are using Abel’s methods, described by Armitage and Eberlein. The key is to start with a non-elementary integral function, differentiating and inverting, and then define a set of functions. Differentiating these functions twice give second-order nonlinear ODEs that have the defined set of functions as solutions. 展开更多
关键词 Non-Elementary Functions Second-Order Nonlinear Autonomous odE
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Multi-Order and Multi-Center Metallogenic Zoning of Yinshan Cu-Au Polymetallic Ore Deposit,Jiangxi Province,China
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作者 Mo Cehui Liu Danying Feng Zhiwen Xia WeflwaChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1993年第1期70-73,共4页
Yinshan anticline is the product of tectono-dynamic deformation - metamorphism .Along the axis of the anticline exists a brittle-ductile shearing zone which obviously controls the ore-formation . Mineralization occurs... Yinshan anticline is the product of tectono-dynamic deformation - metamorphism .Along the axis of the anticline exists a brittle-ductile shearing zone which obviously controls the ore-formation . Mineralization occurs along the axis of the anticline in a width of about 1000m .In the mining area .volcano- subvolcanic rocks of Early Yanshan period are divided into three cycles :Ⅰ intermediate acidic dacite lava and dacite porphyry ;Ⅱ acidic amphibole liparite and quartz porphyry;Ⅲ intermediate andesite porphyrite . Among them activities of ⅠandⅡ cycles are more intensive and are intimately related to the mineralization . Yinshan ore deposit is the result of combinative processes of tectono -dynamic and volcano -magmatic hydrothermal fluids, so that mere are two centers of metallogenic zoning, one being the axial strain zone of Yinshan anticline which is the center of first order, and the other being porphyry stock , 2nd order. 展开更多
关键词 Yinshan polymetallic deposit multi-order and multi-center metallogenic zoning brittle-ductile shearing zone porphyry stock .
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How to Make Systems of Nonlinear Autonomous ODEs with Attractor-Behavior, by First Making the General Solutions: Part Two
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作者 Magne Stensland 《Journal of Applied Mathematics and Physics》 2023年第1期115-134,共20页
This paper is presenting a new method for making first-order systems of nonlinear autonomous ODEs that exhibit limit cycles with a specific geometric shape in two and three dimensions, or systems of ODEs where surface... This paper is presenting a new method for making first-order systems of nonlinear autonomous ODEs that exhibit limit cycles with a specific geometric shape in two and three dimensions, or systems of ODEs where surfaces in three dimensions have attractor behavior. The method is to make the general solutions first by using the exponential function, sine, and cosine. We are building up the general solutions bit for bit according to constant terms that contain the formula of the desired limit cycle, and differentiating them. In Part One, we used only formulas for closed curves where all parts of the formula were of the same degree. In order to use many other formulas for closed curves, the method in this paper is to introduce an additional variable, and we will get an additional ODE. We will choose the part of the formula with the highest degree and multiply the other parts with an extra variable, so that all parts of the formula have the same degree, creating a constant term containing this new formula. We will place it under the fraction line in the solutions, building up the rest of the solutions according to this constant term and differentiating. Keeping this extra variable constant, we will achieve almost the desired result. Using the methods described in this paper, it is possible to make some systems of nonlinear ODEs that are exhibiting limit cycles with a distinct geometric shape in two or three dimensions and some surfaces having attractor behavior, where not all parts of the formulas are the same degree. The pictures show the result. 展开更多
关键词 System of Nonlinear odes Limit Cycle General Solution ATTRACTOR
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Gauss-Legendre Iterative Methods and Their Applications on Nonlinear Systems and BVP-ODEs
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作者 Zhongli Liu Guoqing Sun 《Journal of Applied Mathematics and Physics》 2016年第11期2038-2046,共9页
In this paper, a group of Gauss-Legendre iterative methods with cubic convergence for solving nonlinear systems are proposed. We construct the iterative schemes based on Gauss-Legendre quadrature formula. The cubic co... In this paper, a group of Gauss-Legendre iterative methods with cubic convergence for solving nonlinear systems are proposed. We construct the iterative schemes based on Gauss-Legendre quadrature formula. The cubic convergence and error equation are proved theoretically, and demonstrated numerically. Several numerical examples for solving the system of nonlinear equations and boundary-value problems of nonlinear ordinary differential equations (ODEs) are provided to illustrate the efficiency and performance of the suggested iterative methods. 展开更多
关键词 Iterative Method Gauss-Legendre Quadrature Formula Nonlinear Systems Third-Order Convergence Nonlinear odes
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Skillful Use of Imagery in Two Odes to Spring——Comment on The Soote Season and Spring,the Sweet Spring
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作者 冯海荣 《张家口职业技术学院学报》 2002年第4期26-29,共4页
The Soote Season and Spring,the sweet Spring are two lyrics that sing the praise of spring.The common feature of the two lyrics is that the two poets depict a series of pictures of the sweet spring by rich and varied ... The Soote Season and Spring,the sweet Spring are two lyrics that sing the praise of spring.The common feature of the two lyrics is that the two poets depict a series of pictures of the sweet spring by rich and varied imagery for readers.When these pictures are presented to readers,readers feel as if they are participating in them,and the enchanting beauty of spring makes readers feel intoxicated with happiness.The two poets express their different feelings toward nature. 展开更多
关键词 英语 诗歌 比喻 文学评论 想象力
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