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车辆主动悬架自适应变论域T-S模糊控制研究
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作者 李韶华 季广港 +1 位作者 冯桂珍 王贺 《振动.测试与诊断》 EI CSCD 北大核心 2024年第4期733-739,828,共8页
针对传统变论域模糊控制存在过度依赖专家经验、伸缩因子参数不能自适应调整的问题,提出一种车辆主动悬架自适应变论域T-S模糊控制策略,从而提高车辆的行驶平顺性。结合神经网络和T-S模糊推理建立基于自适应神经模糊推理的一阶T-S模糊... 针对传统变论域模糊控制存在过度依赖专家经验、伸缩因子参数不能自适应调整的问题,提出一种车辆主动悬架自适应变论域T-S模糊控制策略,从而提高车辆的行驶平顺性。结合神经网络和T-S模糊推理建立基于自适应神经模糊推理的一阶T-S模糊控制器,利用神经网络的自学习特性产生完善的模糊规则,进而在传统函数型伸缩因子的基础上,将系统误差和误差变化率作为动态参数引入伸缩因子中,实现伸缩因子参数的自适应调整,解决了传统函数型伸缩因子因参数确定难度大导致控制效果差的问题。通过随机工况下的仿真分析和基于相似理论的缩尺实验,对所提出算法的有效性和工况自适应性进行了验证。结果表明,所提出的自适应变论域T-S模糊控制策略具有较强的工况适应性,在不同车速、路面激励下均可有效提高车辆的平顺性并保证轮胎接地安全性。 展开更多
关键词 主动悬架 变论域 伸缩因子 T-s模糊控制 神经模糊系统
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Symmetry Groups and New Exact Solutions to (2+1)-Dimensional Variable Coefficient Canonical Generalized KP Equation 被引量:7
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作者 ZHANG Li-Hua LIU Xi-Qiang BAI Cheng-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期405-410,共6页
In this paper, the modified CK's direct method to find symmetry groups of nonlinear partial differential equation is extended to (2+1)-dimensional variable coeffficient canonical generalized KP (VCCGKP) equation... In this paper, the modified CK's direct method to find symmetry groups of nonlinear partial differential equation is extended to (2+1)-dimensional variable coeffficient canonical generalized KP (VCCGKP) equation. As a result, symmetry groups, Lie point symmetry group and Lie symmetry for the VCCGKP equation are obtained. In fact, the Lie point symmetry group coincides with that obtained by the standard Lie group approach. Applying the given Lie symmetry, we obtain five types of similarity reductions and a lot of new exact solutions, including hyperbolic function solutions, triangular periodic solutions, Jacobi elliptic function solutions and rational solutions, for the VCCGKP equation. 展开更多
关键词 (2+1)-dimensional variable coefficient canonical generalized KP (VCCGKP) equation modified CK's'direct method symmetry groups Lie symmetry similarity reductions new exact solutions
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An Exponential Series Method for the Solution of Free Convection Boundary Layer Flow in a Saturated Porous Medium
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作者 Vishwanath B Awati N.M Bujurke Ramesh B Kudenatti 《American Journal of Computational Mathematics》 2011年第2期104-110,共7页
Third order nonlinear ordinary differential equation, subject to appropriate boundary conditions, arising in fluid mechanics is solved exactly using more suggestive schemes- Dirichlet series and method of stretching v... Third order nonlinear ordinary differential equation, subject to appropriate boundary conditions, arising in fluid mechanics is solved exactly using more suggestive schemes- Dirichlet series and method of stretching variables. These methods have advantages over pure numerical methods in obtaining derived quantities accurately for various values of the parameters involved at a stretch and are valid in a much larger domain compared with classical numerical schemes. 展开更多
关键词 Boundary Layer Equations sTRETCHING surface DIRICHLET sERIEs Powell’s method sTRETCHING of variables.
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A Comparative Study on Rhetoric of University Commencement Speech⁃es Between China and America
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作者 王普聪 《海外英语》 2020年第17期263-265,共3页
The commencement speech becomes pivotal because it inspires,educates,and enlightens the graduates.Therefore,it is of great value to make a study on the speeches.This article analyzes two commencement speeches between ... The commencement speech becomes pivotal because it inspires,educates,and enlightens the graduates.Therefore,it is of great value to make a study on the speeches.This article analyzes two commencement speeches between China and America from the perspective of rhetoric,namely Aristotle’s appeals as the well as deductive and inductive method of reasoning and finds out that the similarities and differences of those two speeches concerning Aristotle’s appeals as the well as deductive and inductive method of reasoning. 展开更多
关键词 university commencement speech RHETORIC Aristotle’s appeals deductive and inductive method of reasoning
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The Shell Model of the Universe: A Universe Generated from Multiple Big Bangs
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作者 Tower Chen Zeon Chen 《Journal of Modern Physics》 2016年第7期611-626,共16页
The Current Standard Model of the Universe asserts that the universe is generated from a single Big Bang event followed by inflation. There is no center to this universe, hence, no preferential reference frame to desc... The Current Standard Model of the Universe asserts that the universe is generated from a single Big Bang event followed by inflation. There is no center to this universe, hence, no preferential reference frame to describe the motions of celestial objects. We propose a new, Shell Model of the Universe, which contends that the universe is created from multiple, concentric big bangs. Accordingly, that origin presents itself as a unique, preferential reference frame, which furnishes the simplest description of the motions of galaxies in the cosmos. This is similar in manner to how planetary motion is more straightforwardly described via a sun-centered Solar System rather than an earth-centered one. The appeal of the Shell Model of the Universe lies in its simplistic ability to resolve the paradox of quasars, explain the variability in Hubble’s Constant, and solve the problematic accelerated expansion of the universe. 展开更多
关键词 Big Bang Variability in Hubble’s Constant Paradox of Quasars Problematic Accelerated Expansion of the universe
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基于DPRNN语音分离的变时长型S-T课堂教学分析法
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作者 赖文天 陈宇 《湖北第二师范学院学报》 2023年第2期86-92,共7页
在教育智能信息化的大环境下,智能且自动的教学评价体系必不可少,课堂教学分析是教育评价领域的重要环节。本文针对课堂教学分析问题,提出一种利用DPRNN分离课堂音频并使用S-T分析法进行分析的方法。该方法以DPRNN为基础,获取较精确的... 在教育智能信息化的大环境下,智能且自动的教学评价体系必不可少,课堂教学分析是教育评价领域的重要环节。本文针对课堂教学分析问题,提出一种利用DPRNN分离课堂音频并使用S-T分析法进行分析的方法。该方法以DPRNN为基础,获取较精确的教师音频,通过平均细分变时长编码法对音频进行S-T编码处理。相比基于视频的传统的S-T分析法,该方法具有成本低、方便处理、具有时间不变性及准确性较高等优点。 展开更多
关键词 课堂教学分析 DPRNN 平时细分变时长编码法 s-T分析法
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高等教育、区域创新能力与数字经济发展 被引量:10
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作者 孙俊华 万洋 《高校教育管理》 CSSCI 北大核心 2024年第2期1-12,52,共13页
在加快建设数字中国的时代背景下,对高等教育与数字经济之间的关系进行探索有助于优化高等教育的定位和资源配置,并赋能经济社会高质量发展。本研究基于2011—2020年我国各省份的面板数据,实证探究高等教育对区域数字经济发展的影响效... 在加快建设数字中国的时代背景下,对高等教育与数字经济之间的关系进行探索有助于优化高等教育的定位和资源配置,并赋能经济社会高质量发展。本研究基于2011—2020年我国各省份的面板数据,实证探究高等教育对区域数字经济发展的影响效应、作用机制和异质性特征。研究发现,高等教育是区域数字经济发展的重要推动力量,其正向影响效应在使用工具变量缓解内生性问题后仍然稳健;区域创新能力是高等教育驱动数字经济增长的有效机制;高等教育对数字经济的贡献具有明显的时序动态性和区域异质性。基于研究结果,未来我国应彰显数字经济发展中的高校力量,通过探索数字创新人才培养体系、实施差异化产学研融合策略以及优化高等教育资源配置等举措,加快构建高等教育与数字经济协同发展的新格局。 展开更多
关键词 高等教育 数字经济 创新能力 熊彼特创新理论 中介机制模型 工具变量法 熵值法
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Reissner扁球壳开孔的复变函数解法 被引量:2
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作者 胡超 刘殿魁 《哈尔滨电工学院学报》 EI CSCD 1994年第2期114-125,共12页
本文采用弹性厚壳理论及复变函数理论,对Reissner扁球壳开孔问题进行了分析研究,建立了求解厚壳开孔应力集中问题的复变函数解法。若同时采用映射变换,就为求解中厚扁球壳开任意形状孔的应力集中问题提供了一种规范而有效的... 本文采用弹性厚壳理论及复变函数理论,对Reissner扁球壳开孔问题进行了分析研究,建立了求解厚壳开孔应力集中问题的复变函数解法。若同时采用映射变换,就为求解中厚扁球壳开任意形状孔的应力集中问题提供了一种规范而有效的方法。 展开更多
关键词 扁球壳 开孔 复变函数
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超高强度抽油杆P-S-N曲线拟合新方法 被引量:3
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作者 胥元刚 郝帆帆 《石油钻采工艺》 CAS CSCD 北大核心 2017年第3期334-337,共4页
P-S-N曲线是超高强度抽油杆力学性能分析的主要依据,其拟合方法通常参照于普通抽油杆。然而实验数据表明,超高强度抽油杆并不满足普通抽油杆P-S-N曲线拟合模型的假设条件。为了研究适应于超高强度抽油杆的P-S-N曲线拟合方法,提出了基于B... P-S-N曲线是超高强度抽油杆力学性能分析的主要依据,其拟合方法通常参照于普通抽油杆。然而实验数据表明,超高强度抽油杆并不满足普通抽油杆P-S-N曲线拟合模型的假设条件。为了研究适应于超高强度抽油杆的P-S-N曲线拟合方法,提出了基于Box-Cox变量变换法的三参数P-S-N曲线拟合模型,其中Box-Cox变量变换法解决了一定循环应力下,疲劳寿命不满足正态分布的问题;三参数P-S-N曲线模型更符合典型S-N曲线的趋势。实验计算结果表明,新方法下的P-S-N曲线拟合度更高,相对误差仅为1.46%~4.12%,仅为以往方法的11%~30%,新方法拟合的曲线更能体现超高强度抽油杆力学性能,精确度更高。 展开更多
关键词 P-s-N曲线 超高强度 抽油杆 Box-Cox变量变换法
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浅析美国名校视频公开课教学模式及对中国高校的启示——基于S-T教学分析法 被引量:13
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作者 花春叶 《南宁职业技术学院学报》 2012年第2期40-43,共4页
美国名校视频公开课是一种国际教育资源开放与共享的教学模式。通过运用S-T教学分析法,对其进行量化的教学过程进行评估,研究不同教学模式的特点和不足,比如讲授型教学模式、混合型教学模式、辩证看待教学模式,为中国高校深化建构主义... 美国名校视频公开课是一种国际教育资源开放与共享的教学模式。通过运用S-T教学分析法,对其进行量化的教学过程进行评估,研究不同教学模式的特点和不足,比如讲授型教学模式、混合型教学模式、辩证看待教学模式,为中国高校深化建构主义理念教学、加强网络信息化教学、强化尊重学生的理念等提供参考。 展开更多
关键词 s-T分析法 美国名校 视频公开课 教学模式
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“U-S”共同体下小学语文教学法实践教学改革初探 被引量:11
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作者 韦芳 《河池学院学报》 2013年第4期104-110,共7页
针对高校小学教育专业师范生教学实践能力薄弱的问题,在小学语文教学法教学中需建构"US"共同体(大学与小学合作),进行"实践取向"的课堂教学、教育见习与教师角色体验、模拟教学实践、实习支教前技能强化训练、教育... 针对高校小学教育专业师范生教学实践能力薄弱的问题,在小学语文教学法教学中需建构"US"共同体(大学与小学合作),进行"实践取向"的课堂教学、教育见习与教师角色体验、模拟教学实践、实习支教前技能强化训练、教育实习与教育情境研究等多样化实践教学的探索,有效地促进了师范生培养自我职业生涯规划意识与训练小学语文教学技能,还促进师范生去研习小学语文新课程教学改革,为培养合格的小学语文教师发挥了积极作用。 展开更多
关键词 “U—s”共同体 小学语文教学法 实践教学 教师教育 高校 师范生
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基于S-函数改进电导法的光伏阵列最大功率点的跟踪 被引量:2
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作者 蔺娜 刘星 葛晨 《西北水电》 2014年第2期90-92,99,共4页
光伏阵列最大功率点的控制策略是光伏递变器研究的重点之一,文章在深入研究传统电导增量法工作原理的基础上,提出一种基于S-函数的恒电压启动的变步长电导增量法来实现最大功率点跟踪,并在MATLAB/Simulink环境下搭建了光伏阵列的仿真模... 光伏阵列最大功率点的控制策略是光伏递变器研究的重点之一,文章在深入研究传统电导增量法工作原理的基础上,提出一种基于S-函数的恒电压启动的变步长电导增量法来实现最大功率点跟踪,并在MATLAB/Simulink环境下搭建了光伏阵列的仿真模型,通过对比仿真结果可以证明,改进的电导增量法能够准确地反映出光伏阵列输出电压和电流的非线性特性,并且能快速高效地跟踪最大功率点。 展开更多
关键词 光伏阵列 最大功率点 跟踪 s-函数 电导增量法 恒电压变步长
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Anisotropic Bianchi Type-I Magnetized String Cosmological Models with Decaying Vacuum Energy Density A(t)
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作者 Anirudh Pradhan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第5期931-941,共11页
The present study deals with a spatially homogeneous and anisotropic Bianehi-I cosmological models representing massive strings with magnetic field and decaying vacuum energy density A. The energy-momentum tensor, as ... The present study deals with a spatially homogeneous and anisotropic Bianehi-I cosmological models representing massive strings with magnetic field and decaying vacuum energy density A. The energy-momentum tensor, as formulated by Letelier (1983), has been used to construct massive string cosmological models for which we assume the expansion scalar in the models is proportional to one of the components of shear tensor. The Einstein's field equations have been solved by applying a variation law for generalized Hubble's parameter in Bianchi-I space-time. The variation law for Hubble's parameter generates two types of solutions for the average scale factor, one is of power-law type and other is of the exponential form. Using these two forms, Einstein's field equations are solved separately that correspond to expanding singular and non-singular models of the universe respectively. We have made a comparative study of accelerating and decelerating models in the presence of string scenario. The study reveals that massive strings dominate in the decelerating universe whereas strings dominate in the accelerating universe. The strings eventually disappear from the universe for sufficiently large times, which is in agreement with current astronomical observations. The cosmological constant A is found to be a positive decreasing function of time which is corroborated by results from recent supernovae Ia observations. The physical and geometric properties of the models have been also discussed in detail. 展开更多
关键词 cosmic strings Bianchi-I universe variable cosmological constant Hubble's parameter
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Parkinsonian oscillations and their suppression by closed-loop deep brain stimulation based on fuzzy concept
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作者 Xi-Le Wei Yu-Lin Bai +2 位作者 Jiang Wang Si-Yuan Chang Chen Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第12期684-691,共8页
This paper provides an adaptive closed-loop strategy for suppressing the pathological oscillations of the basal ganglia based on a variable universe fuzzy algorithm.The pathological basal ganglia oscillations in the t... This paper provides an adaptive closed-loop strategy for suppressing the pathological oscillations of the basal ganglia based on a variable universe fuzzy algorithm.The pathological basal ganglia oscillations in the theta(4-9 Hz)and beta(12-35 Hz)frequency bands have been demonstrated to be associated with the tremor and rigidity/bradykinesia symptoms in Parkinson’s disease(PD).Although the clinical application of open-loop deep brain stimulation(DBS)is effective,the stimulation waveform with the fixed parameters cannot be self-adjusted as the disease progresses,and thus the stimulation effects go poor.To deal with this difficult problem,a variable universe fuzzy closed-loop strategy is proposed to modulate different PD states.We establish a cortico-basal ganglia-thalamocortical network model to simulate pathological oscillations and test the control effect.The results suggest that the proposed closed-loop control strategy can accommodate the variation of brain states and symptoms,which may become an alternative method to administrate the symptoms in PD. 展开更多
关键词 deep brain stimulation Parkinson’s disease basal ganglia closed-loop control variable universe fuzzy
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Closed form solution and numerical analysis for Eshelby's elliptic inclusion in plane elasticity
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作者 陈宜周 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第7期863-874,共12页
This paper presents a closed form solution and numerical analysis for Es- helby's elliptic inclusion in an infinite plate. The complex variable method and the confor- real mapping technique are used. The continuity c... This paper presents a closed form solution and numerical analysis for Es- helby's elliptic inclusion in an infinite plate. The complex variable method and the confor- real mapping technique are used. The continuity conditions for the traction and displace- ment along the interface in the physical plane are reduced to the similar conditions along the unit circle of the mapping plane. The properties of the complex potentials defined in the finite elliptic region are analyzed. From the continuity conditions, one can separate and obtain the relevant complex potentials defined in the inclusion and the matrix. From the obtained complex potentials, the dependence of the real strains and stresses in the inclusion from the assumed eigenstrains is evaluated. In addition, the stress distribution on the interface along the matrix side is evaluated. The results are obtained in the paper for the first time. 展开更多
关键词 Eshelby's elliptic inclusion complex variable method closed form solution
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Torsion of Circular Shaft with Elliptical Inclusions or Cracks
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作者 HUANG Cheng YIN Maoshu +1 位作者 QI Xiao GUO Hun 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第1期96-105,共10页
This paper proposes a straightforward and concise approach to analyze the Saint-Venant’s torsion of a circular shaft containing multiple elliptical inclusions or cracks based on the complex variable method.The comple... This paper proposes a straightforward and concise approach to analyze the Saint-Venant’s torsion of a circular shaft containing multiple elliptical inclusions or cracks based on the complex variable method.The complex potentials are first derived for the shaft with N elliptical inclusions by introducing Faber series expansion,and then the shear stresses and torsional rigidity are calculated.When the inclusions degenerate into cracks,the solutions for the intensity factors of stress are obtained.Finally,several numerical examples are carried out to discuss the effects of geometry parameters,different shear modulus ratios and array-types of the elliptical inclusions/cracks on the fields of stresses.The obtained results show that the proposed approach has advantages such as high accuracy and good convergence. 展开更多
关键词 saint-Venant’s torsion complex variable method Faber series
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Riemann Hypothesis, Catholic Information and Potential of Events with New Techniques for Financial and Other Applications
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作者 Prodromos Char. Papadopoulos 《Advances in Pure Mathematics》 2021年第5期524-572,共49页
In this research we are going to define two new concepts: a) “The Potential of Events” (EP) and b) “The Catholic Information” (CI). The term CI derives from the ancient Greek language and declares all the Catholic... In this research we are going to define two new concepts: a) “The Potential of Events” (EP) and b) “The Catholic Information” (CI). The term CI derives from the ancient Greek language and declares all the Catholic (general) Logical Propositions (<img src="Edit_5f13a4a5-abc6-4bc5-9e4c-4ff981627b2a.png" width="33" height="21" alt="" />) which will true for every element of a set A. We will study the Riemann Hypothesis in two stages: a) By using the EP we will prove that the distribution of events e (even) and o (odd) of Square Free Numbers (SFN) on the axis Ax(N) of naturals is Heads-Tails (H-T) type. b) By using the CI we will explain the way that the distribution of prime numbers can be correlated with the non-trivial zeros of the function <em>ζ</em>(<em>s</em>) of Riemann. The Introduction and the Chapter 2 are necessary for understanding the solution. In the Chapter 3 we will present a simple method of forecasting in many very useful applications (e.g. financial, technological, medical, social, etc) developing a generalization of this new, proven here, theory which we finally apply to the solution of RH. The following Introduction as well the Results with the Discussion at the end shed light about the possibility of the proof of all the above. The article consists of 9 chapters that are numbered by 1, 2, …, 9. 展开更多
关键词 Twin Problem Twin’s Problem Unsolved Mathematical Problems Prime Number Problems Millennium Problems Riemann Hypothesis Riemann’s Hypothesis Number Theory Information Theory Probabilities statistics Management Financial Applications Arithmetical Analysis Optimization Theory stock Exchange Mathematics Approximation methods Manifolds Economical Mathematics Random variables space of Events strategy Games Probability Density stock Market Technical Analysis Forecasting
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变权重组合S型曲线在路面平整度预测中的应用
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作者 何怀平 余自力 《公路工程》 2008年第4期125-128,共4页
通过对路面平整度指数IRI随时间发展规律及其特点的分析与研究,得出平整度的发展基本经历了先慢后快再慢的过程,基于3种"S"型增长曲线模型,提出一种预测路面平整度发展规律的变权重组合预测方法,并建立了变权重组合"S&qu... 通过对路面平整度指数IRI随时间发展规律及其特点的分析与研究,得出平整度的发展基本经历了先慢后快再慢的过程,基于3种"S"型增长曲线模型,提出一种预测路面平整度发展规律的变权重组合预测方法,并建立了变权重组合"S"型增长模型,从而可根据有限的实测平整度观测数据预测路面平整度的发展过程。工程实例分析结果表明,使用该模型,其预测曲线与实测数据曲线基本吻合,可用于路面平整度的预测,为解决我国平整度模型预测精度不高提供一种有效而实用的方法。 展开更多
关键词 国际平整度指数 变权重组合预测 s型增长曲线 预测方法
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基于男装制版法的休闲女西装结构设计 被引量:3
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作者 罗静 柴莉 《毛纺科技》 CAS 北大核心 2023年第1期56-63,共8页
为优化休闲女西装样板风格和提高制版效率,解决传统女西装制版法公式变量多,制版步骤较复杂的问题,以经典款三开身休闲女西装为例,通过男装结构设计方法探讨休闲女西装的结构影响因素。采用CLO3D试衣软件分析了基于男装制版法的休闲女... 为优化休闲女西装样板风格和提高制版效率,解决传统女西装制版法公式变量多,制版步骤较复杂的问题,以经典款三开身休闲女西装为例,通过男装结构设计方法探讨休闲女西装的结构影响因素。采用CLO3D试衣软件分析了基于男装制版法的休闲女西装前胸宽、后背宽、袖窿宽三者的配比关系,得出标准A体前胸宽调节数和后背宽调节数的最佳取值范围。以真人着装实验验证了休闲女西装采用男装制版法设计的可行性,并从制版效率和样板风格对比说明采用男装制版法进行休闲款女装结构设计的优势,为企业生产休闲款、大廓形款和中性化风格一类的女装提供良好的制版思路。 展开更多
关键词 休闲女西装 结构设计 男装制版法 调节数 服装设计
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Ulam-Hyers stability and analytical approach for m-dimensional Caputo space-time variable fractional order advection-dispersion equation
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作者 Pratibha Verma Manoj Kumar Anand Shukla 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2022年第1期131-174,共44页
This article introduces the computational analytical approach to solve the m-dimensional space-time variable Caputo fractional order advection–dispersion equation with the Dirichlet boundary using the two-step Adomia... This article introduces the computational analytical approach to solve the m-dimensional space-time variable Caputo fractional order advection–dispersion equation with the Dirichlet boundary using the two-step Adomian decomposition method and obtain the exact solution in just one iteration.Moreover,with the help of fixed point theory,we study the existence and uniqueness conditions for the positive solution and prove some new results.Also,obtain the Ulam–Hyers stabilities for the proposed problem.Two gen-eralized examples are considered to show the method’s applicability and compared with other existing numerical methods.The present method performs exceptionally well in terms of efficiency and simplicity.Further,we solved both examples using the two most well-known numerical methods and compared them with the TSADM solution. 展开更多
关键词 Fixed point theorems space-time variable Caputo’s fractional operators advection-dispersion equation Ulam-Hyers stability two-step Adomian decomposition method
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