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基于注意力增强Uniformer的锂电池剩余使用寿命预测
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作者 廖列法 刘映宝 占玉敏 《汽车技术》 北大核心 2025年第6期36-44,共9页
针对锂离子电池的剩余使用寿命(RUL)预测时常面临数据的动态变化和老化数据有限的问题,提出注意力增强Uniformer(AEUniformer)的RUL预测模型,通过Uniformer整合卷积神经网络(CNN)和自注意力机制的优势实现全面的信息感知;设计注意力引... 针对锂离子电池的剩余使用寿命(RUL)预测时常面临数据的动态变化和老化数据有限的问题,提出注意力增强Uniformer(AEUniformer)的RUL预测模型,通过Uniformer整合卷积神经网络(CNN)和自注意力机制的优势实现全面的信息感知;设计注意力引导机制(AGM)和CoordAttention实现强大的特征提取。试验结果表明,AEUniformer可以实现仅需单个老化周期的准确快速的RUL预测,数据集的平均绝对百分比误差分别为2.7%和6.16%,证明了该方法的准确性。 展开更多
关键词 锂电池 剩余使用寿命预测 数据驱动 统一变形器 注意力引导机制 坐标注意力
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THE SPECTRAL RADIUS OF UNIFORM HYPERGRAPH DETERMINED BY THE SIGNLESS LAPLACIAN MATRIX
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作者 HE Fang-guo 《数学杂志》 2025年第1期1-12,共12页
This paper studies the problem of the spectral radius of the uniform hypergraph determined by the signless Laplacian matrix.The upper bound of the spectral radius of a uniform hypergraph is obtained by using Rayleigh ... This paper studies the problem of the spectral radius of the uniform hypergraph determined by the signless Laplacian matrix.The upper bound of the spectral radius of a uniform hypergraph is obtained by using Rayleigh principle and the perturbation of the spectral radius under moving the edge operation,and the extremal hypergraphs are characterized for both supertree and unicyclic hypergraphs.The spectral radius of the graph is generalized. 展开更多
关键词 spectral radius uniform hypergraph Signless Laplasian matrix
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An improved time integration scheme based on uniform cubic B-splines and its application in structural dynamics
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作者 Weibin WEN Hongshuai LEI +3 位作者 Kai WEI Baosheng XU Shengyu DUAN Daining FANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第6期889-908,共20页
A time integration algorithm for structural dynamic analysis is proposed by uniform cubic B-spline functions. The proposed algorithm is successfully used to solve the dynamic response of a single degree of freedom (S... A time integration algorithm for structural dynamic analysis is proposed by uniform cubic B-spline functions. The proposed algorithm is successfully used to solve the dynamic response of a single degree of freedom (SDOF) system, and then is generalized for a multiple-degree of freedom (MDOF) system. Stability analysis shows that, with an adjustable algorithmic parameter, the proposed method can achieve both conditional and unconditional stabilities. Validity of the method is shown with four numerical simulations. Comparison between the proposed method and other methods shows that the proposed method possesses high computation accuracy and desirable computation efficiency. 展开更多
关键词 dynamical system time integration~ stability dynamic response b-spline
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On Non-Uniform Algebraic-Hyperbolic (NUAH) B-Splines 被引量:1
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作者 Jiang Qian Yuehong Tang 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第4期320-335,共16页
The recurrence algorithm is given for the calculation of NUAH B-splines in the space Sn+1 = span{sinh t, cosh t,tn-3,...,t2.t, 1} (n≥3). The case of NUAH B-spline bases of low order with multiple knot sequences is st... The recurrence algorithm is given for the calculation of NUAH B-splines in the space Sn+1 = span{sinh t, cosh t,tn-3,...,t2.t, 1} (n≥3). The case of NUAH B-spline bases of low order with multiple knot sequences is studied. The limiting cases of UAH B-splines are recovered when shape parameters a's→0+and+∞. Then the corresponding NUAH B-spline curve is defined and its main properties such as shape-preserving properties are investigated. 展开更多
关键词 非统一代数-双曲线B样条 统一B样条 凸性保存 形状保存
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Extraction of Feature Points for Non-Uniform Rational B-Splines(NURBS)-Based Modeling of Human Legs
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作者 WANG Xi WU Zongqian LI Qiao 《Journal of Donghua University(English Edition)》 CAS 2022年第4期299-303,共5页
Methods of digital human modeling have been developed and utilized to reflect human shape features.However,most of published works focused on dynamic visualization or fashion design,instead of high-accuracy modeling,w... Methods of digital human modeling have been developed and utilized to reflect human shape features.However,most of published works focused on dynamic visualization or fashion design,instead of high-accuracy modeling,which was strongly demanded by medical or rehabilitation scenarios.Prior to a high-accuracy modeling of human legs based on non-uniform rational B-splines(NURBS),the method of extracting the required quasi-grid network of feature points for human legs is presented in this work.Given the 3 D scanned human body,the leg is firstly segmented and put in standardized position.Then re-sampling of the leg is conducted via a set of equidistant cross sections.Through analysis of leg circumferences and circumferential curvature,the characteristic sections of the leg as well as the characteristic points on the sections are then identified according to the human anatomy and shape features.The obtained collection can be arranged to form a grid of data points for knots calculation and high-accuracy shape reconstruction in future work. 展开更多
关键词 3D scan digital human modeling non-uniform rational b-splines(NURBS) feature extraction
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Adaptive-basis decomposition-based low-rank network for efficient non-uniform motion deblurring
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作者 CHEN Lei XIONG Qingbo +1 位作者 ZHANG Wei LI Runde 《Optoelectronics Letters》 2025年第1期43-50,共8页
In this study,we present a unified sparsity-driven framework that significantly enhances motion deblurring performance by integrating two key components:a custom-designed dataset and a low-rank module(LRM).This framew... In this study,we present a unified sparsity-driven framework that significantly enhances motion deblurring performance by integrating two key components:a custom-designed dataset and a low-rank module(LRM).This framework leverages the inherent sparsity of per-pixel blur kernels to bolster both deblurring accuracy and model interpretability.Firstly,we propose an adaptive-basis decomposition-based deblurring(ADD)approach,which constructs a tailored training dataset to enhance the generalization capacity of the deblurring network.The ADD framework adaptively decomposes motion blur into sparse basis elements,effectively addressing the intricacies associated with non-uniform blurs.Secondly,an LRM is proposed to improve the interpretability of deblurring models as a plug-and-play module,primarily designed to identify and harness the intrinsic sparse features in sharp images.A series of ablation studies have been conducted to substantiate the synergistic advantages of combining the proposed ADD with the LRM for overall improvement in deblurring efficacy.Subsequently,we empirically demonstrate through rigorous experimentation that incorporating the LRM into an existing Uformer network leads to substantial enhancement in reconstruction performance.This integration yields a sparsity-guided low-rank network(SGLRN).Operating under the overarching principle of sparsity,SGLRN consistently outperforms state-of-the-art methods across multiple standard deblurring benchmarks.Comprehensive experimental results,assessed through quantitative metrics and qualitative visual evaluations,provide compelling evidence of its effectiveness.The overall deblurring results are available at Google Drive. 展开更多
关键词 NETWORK motion uniform
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My Views on School Uniforms
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作者 徐迪迪 《中学生英语》 2025年第18期6-6,共1页
At our school,we have to wear uniforms every day.The problem is that all my classmates think the uniforms are ugly.We think young people should look smart,because①we would like to wear our own clothes.Our teachers th... At our school,we have to wear uniforms every day.The problem is that all my classmates think the uniforms are ugly.We think young people should look smart,because①we would like to wear our own clothes.Our teachers think that if we do that,we will concentrate much②on our clothes than our studies.We don't agree. 展开更多
关键词 STUDIES school uniforms CLOTHING APPEARANCE
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基于B-spline曲线的通风机多维度协同优化
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作者 蒋山杰 高全杰 +2 位作者 郭时敏 孙志波 曾锦荣 《暖通空调》 2025年第9期57-63,27,共8页
通风机在暖通空调系统中发挥着关键作用,主要用于送风、补风和通风。目前对建筑用通风机的研究仍存在模型复杂、计算困难的问题。本文提出利用多维度协同优化设计方法来优化通风机的气动性能。在优化设计过程中,采用B-spline曲线参数化... 通风机在暖通空调系统中发挥着关键作用,主要用于送风、补风和通风。目前对建筑用通风机的研究仍存在模型复杂、计算困难的问题。本文提出利用多维度协同优化设计方法来优化通风机的气动性能。在优化设计过程中,采用B-spline曲线参数化叶片表面形状,通过流场降维处理,在搭建的自动化平台上进行多目标优化进而筛选高效细化区间,继而在该区间内实施最优拉丁超立方抽样。基于样本的计算流体力学模拟结果表明,最优解的通风机压力和叶轮力矩分别为742.44 Pa和174.12 N,与原始方案相比,在保持通风机压力变化不大的同时叶轮力矩降低了16.33%,通风机效率提升了19.60%。该方法显著降低了方案寻优的成本,为通风机的性能评估提供了便利。 展开更多
关键词 b-spline曲线 离心通风机 多维度协同优化 NSGA-Ⅱ 气动性能 叶轮
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Theoretical and Experimental Investigations on Thickness Uniformity in Double-sided Lapping
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作者 Zhuolin Cai Zhe Yang +4 位作者 Bo Pan Jiale Lian Lianlin Wang Sergei Pronkevich Jiang Guo 《Chinese Journal of Mechanical Engineering》 2025年第3期151-163,共13页
The double-sided lapping process is extensively employed in the manufacturing of wafers,optical windows,and seal rings due to its high efficiency and ability to achieve precise flatness.However,limited research has ex... The double-sided lapping process is extensively employed in the manufacturing of wafers,optical windows,and seal rings due to its high efficiency and ability to achieve precise flatness.However,limited research has explored the thickness uniformity among different workpieces after double-sided lapping,and the underlying mechanism remains unclear.To address the demand for higher precision,this paper first analyzed the relative kinematic model between the workpiece and the lapping plate to clarify the causes of thickness variations among workpieces after double-sided lapping.Subsequently,a finite element method(FEM)model was developed to account for the pressure distribution on the workpiece surfaces at the initial stage of the process.The results indicate that the number of workpieces influences the final thickness variation.Then,various sets of thin copper plates with different thicknesses were lapped,and the findings revealed that five copper plates processed simultaneously exhibited more uniform thickness compared to the three plates.The experimental results align well with the theoretical analysis.Ultimately,a thickness variation of less than 6μm was achieved on five copper plates measuringΦ100×2.9 mm.This study presents a comprehensive analysis of the mechanisms influencing thickness uniformity in the double-sided lapping process and provides practical guidelines for optimizing the process to achieve stringent precision standards in industrial applications. 展开更多
关键词 Double-sided lapping Thickness uniformity Theoretical analysis FEM Thin copper plate
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Uniformity of microbial injection for reinforcing saturated calcareous sand: A multi-test approach
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作者 Xinlei Zhang Yue Sun +3 位作者 Yumin Chen Lu Liu Wenwen Li Yi Han 《Biogeotechnics》 2025年第2期52-61,共10页
The mineralization process of microbial-induced calcium carbonate precipitation(MICP)is influenced by many factors,and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for ... The mineralization process of microbial-induced calcium carbonate precipitation(MICP)is influenced by many factors,and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for MICP technology.In this study,the uniformity of the saturated calcareous sand treated with MICP was in-vestigated through one-dimensional calcareous sand column tests and model tests.The coefficient of variation was employed in one-dimensional sand column tests to investigate the impact of injection rate,cementation solution concentration,and number of injection cycles on the uniformity of the MICP treatment.Additionally,model tests were conducted to investigate the impact of injection pressure and methods on the treatment range and uniformity under three-dimensional seepage conditions.Test results demonstrate that the reinforcement strength and uniformity are significantly influenced by the injection rate of the cementation solution,with a rate of 3 mL/min,yielding a favorable treatment effect.Excessive concentration of the cementation solution can lead to significant non-uniformity and a reduction in the compressive strength of MICP-treated samples.Conversely,excessively low concentrations may result in decreased bonding efficiency.Among the four considered con-centrations,0.5 mol/L and 1 mol/L exhibit superior reinforcing effects.The morphological development of calcareous sandy foundation reinforcement is associated with the spatial distribution pattern of the bacterial solution,exhibiting a relatively larger reinforcement area in proximity to the lower region of the model and a gradually decreasing range towards the upper part.Under three-dimensional seepage conditions,in addition to the non-uniform radial cementation along the injection pipe,there is also vertical heterogeneity of cementation along the length of the injection pipe due to gravitational effects,resulting in preferential deposition of calcium carbonate at the lower section,The application of injection pressure and a double-pipe circulation injection method can mitigate the accumulation of bacterial solution and cementation solution at the bottom,thereby improving the reinforcement range and uniformity. 展开更多
关键词 MICP Calcareous sand Reinforcement uniformity One-dimensional sand column tests Model tests
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Improvement of Mechanical Properties and Wall Thickness Uniformity of Hollow Ceramic Spheres by Biaxial Rotation Slurry Injection Technology
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作者 WANG Qiuyang ZHOU Jian +2 位作者 LIU Guizhen WANG Lin DING Zhongjun 《Journal of Wuhan University of Technology(Materials Science)》 2025年第3期619-626,共8页
Ceramic hollow spheres have great potential for deep-sea applications.However,the irregularity of the conventional molding process,among other reasons,results in low wall thickness uniformity of hollow spheres.To solv... Ceramic hollow spheres have great potential for deep-sea applications.However,the irregularity of the conventional molding process,among other reasons,results in low wall thickness uniformity of hollow spheres.To solve this problem,in this work,we developed a biaxial rotation grouting process for deep-sea ceramic hollow buoyancy spheres,which improves the drawbacks of the traditional rotary grouting method that results in poor wall thickness uniformity of the hollow spheres due to its irregular rotational processing.In this paper,an experimental study was carried out to investigate the effects of different rotational methods,rotational speeds,rotational time,solid phase content,etc.on the wall thickness uniformity of ceramic hollow spheres.The results show that the hollow floating balls prepared by the biaxial rotation method have the lowest wall thickness standard deviation(0.04)when the rotation speed is 60 rpm,the molding time is 8 min,and the solid phase content is 70 wt%.After the hydrostatic pressure test of 120 MPa,the hydrostatic compressive strength of hollow spheres prepared by the biaxial rotation method was increased by 31.67%compared with that of the traditional process. 展开更多
关键词 ceramic hollow sphere biaxial rotation monolithic molding wall thickness uniformity
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Degradation of fully saturated uniform sand subjected to small-strain undrained cyclic shearing
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作者 Vedran Jagodnik Tea Sulovsky 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第10期6662-6677,共16页
In soil dynamics,cyclic tests on sands have been extensively studied over the past several decades.Among the natural materials most susceptible to strength loss due to earthquakes,sands are commonly tested under varyi... In soil dynamics,cyclic tests on sands have been extensively studied over the past several decades.Among the natural materials most susceptible to strength loss due to earthquakes,sands are commonly tested under varying loading,frequency,and drainage conditions.Traditionally,it has been assumed that pore pressure increases with constant strength loss once the threshold for pore pressure build-up is reached.However,recent studies have revealed that at small strains,the material initially hardens despite the generation of pore pressure.This paper presents the response and degradation of uniformly graded Drava River sand(DrOS018),similar to well-known sands such as Toyoura,Nevada or Ottawa sands,and the initial hardening phenomena that occur around threshold strains.Tests were conducted using a triaxial cyclic device at three relative densities and cell pressures(100 kPa,200 kPa,and 400 kPa)under undrained conditions.Strain-controlled tests were conducted at 0.1 Hz and 0.05 Hz using sinusoidal loading,with samples prepared by under-compaction.After crossing the threshold,the sand initially shows hardening(degradation index greater than 1)with up to a 35%increase in pore pressure,followed by strength degradation at higher strains.This study is critical for seismic design and safety,particularly for fully saturated sands in coastal and high water table areas.The findings enhance our understanding of liquefaction potential and site response,aiding more informed engineering practices by contributing to enhanced knowledge in soil dynamics and improved predictive models.The results support effective mitigation strategies and infrastructure resilience in earthquake-prone regions such as Croatia. 展开更多
关键词 Cyclic triaxial test uniform drava river sand Degradation index Normalized pore water pressure
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Seeking Harmony without Uniformity in Mutual Learning: Diversity of Civilisations from the Sinologists' Perspective
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《International Understanding》 2025年第2期28-29,共2页
On the morning of May 31st,the parallel forum"Seeking Harmony without Uniformity in Mutual Learning:Diversity of Civilisations from the Sinologists'Perspective"was held in Dunhuang.The forum was hosted b... On the morning of May 31st,the parallel forum"Seeking Harmony without Uniformity in Mutual Learning:Diversity of Civilisations from the Sinologists'Perspective"was held in Dunhuang.The forum was hosted by the Chinese Association for International Understanding and organised by Beijing Language and Culture University.Leading Sinologists and Chinese culture researchers from Europe,Asia and Latin America gathered to discuss the theme of civilisational diversity and explore pathways for coexistence and mutual enrichment. 展开更多
关键词 mutual learning civilisations parallel forum civilisational diversity diversity civilizations parallel forumseeking chinese culture researchers harmony uniformity
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Characteristics of Heat Transfer in a Reactive Third-Grade Fluid Flow through Porous Plates with Uniform Suction/Injection
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作者 Rajiva Lochan Mohanty Sumanta Chaudhuri Anish Pandey 《Frontiers in Heat and Mass Transfer》 2025年第3期899-919,共21页
Characteristics of heat transfer and flow of Newtonian and non-Newtonian fluids through porous walls and in porous media are studied due to their wide range of applications including geothermal reservoirs,heat exchang... Characteristics of heat transfer and flow of Newtonian and non-Newtonian fluids through porous walls and in porous media are studied due to their wide range of applications including geothermal reservoirs,heat exchangers,marine propulsion,and aerodynamics.The current study investigates the characteristics of heat transport in a reactive third-grade fluid,moving through permeable parallel plates,with uniform suction/injection velocity.The two permeable,parallel plates are maintained at the same,constant temperature.After being transformed into its dimensionless equivalent,governing equations are solved by employing the Least Squares Method(LSM).The LSM results are further validated with numerical solutions for temperature and velocity.The impact of cross-flow Reynolds number,Peclet number,heat generation parameter,non-Newtonian parameter,and Brinkman number on entropy generation,velocity,temperature,and Bejan number are investigated.Theresults indicate that temperature distribution is significantly influenced by the third-grade fluid parameter.The maximum temperature drops from almost 0.12 to 0.10 as the third-grade fluid parameter increases from0.05 to 0.4.When the cross-flow Reynolds number is raised from 0.05 to 3,the maximum temperature drops from 0.12 to around 0.09.Temperature is strongly influenced by the heat generation parameter.A greater understanding of the thermal characteristics necessary for the design of a variety of systems,such as heat exchangers,marine propulsion,aerodynamic systems,etc.,may be gained from the findings of the current study. 展开更多
关键词 Heat generation third grade fluids perturbation method least square method uniform suction/injection porous plates
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Two-dimensional plane-strain consolidation for unsaturated soils under non-uniform trapezoidal loads
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作者 Chengjia TANG Lei WANG +2 位作者 Sidong SHEN Minjie WEN Annan ZHOU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第3期277-284,共8页
1 Introduction In highway construction,flled embankments are trapezoidal,and the ground is always improved by sand wells or columns.During embankment construction,because the width and height of the embankment are cha... 1 Introduction In highway construction,flled embankments are trapezoidal,and the ground is always improved by sand wells or columns.During embankment construction,because the width and height of the embankment are changing,a non-uniform load that varies with time and lateral location is applied to the underlying ground.The consolidation phenomenon under two-dimensional(2D)conditions will keep pace with the construction of the embankment.In addition,because of evaporation and rainfall,the soils are mostly unsaturated.Therefore,it is meaningful to research the consolidation properties of unsaturated ground under non-uniform loading. 展开更多
关键词 two dimensional plane strain consolidation highway construction sand wells embankment construction consolidation phenomenon unsaturated soils non uniform trapezoidal loads
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利用B-splines特性计算PbS量子点中的激子基态能量的量子尺寸效应 被引量:3
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作者 惠萍 《计算物理》 CSCD 北大核心 2007年第6期753-756,共4页
利用B-splines特性构建量子点中激子的波函数,计算PbS量子点中激子的基态能量Eg的量子尺寸效应,并将计算结果与实验结果及其他理论计算结果进行比较;利用B-splines技术计算的激子的基态能量在整个区域与实验完全符合,同时计算了有效质... 利用B-splines特性构建量子点中激子的波函数,计算PbS量子点中激子的基态能量Eg的量子尺寸效应,并将计算结果与实验结果及其他理论计算结果进行比较;利用B-splines技术计算的激子的基态能量在整个区域与实验完全符合,同时计算了有效质量和势垒高度对基态能量Eg的量子尺寸效应的影响. 展开更多
关键词 b-splines 量子点 基态能量 量子尺寸效应 有效质量
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用B-splines技术计算超强平行外磁场中氢分子离子的能级 被引量:3
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作者 惠萍 《计算物理》 EI CSCD 北大核心 2010年第3期451-456,共6页
考虑两核之间的相互作用,采用单中心展开方法和B-splines技术构建氢分子离子的径向和角向波函数,计算超强平行外磁场中氢分子离子的能级Eb(m=0,-1,-2,-3,-4,-5)和两核间的平衡距离2R.计算中,磁场强度从2.35×106T变到2.35×108T... 考虑两核之间的相互作用,采用单中心展开方法和B-splines技术构建氢分子离子的径向和角向波函数,计算超强平行外磁场中氢分子离子的能级Eb(m=0,-1,-2,-3,-4,-5)和两核间的平衡距离2R.计算中,磁场强度从2.35×106T变到2.35×108T.对比绝热变分近似计算结果,计算精度提高的范围在0.00015Ry~0.0488Ry之间;对比变分近似计算结果,计算精度提高的范围在0.0029Ry~0.0257Ry之间.这些计算结果表明,用二重B-splines基函数展开方法使氢分子离子的波函数的完备性更好,并能得到比绝热变分近似和绝热近似方法更高的计算精度. 展开更多
关键词 氢分子离子 b-spline技术 超强平行外磁场 绝热变分近似
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基于B-Splines网络的飞行姿态控制器设计
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作者 秦硕 孙秀霞 +2 位作者 薛建平 张渤雨 成万舟 《飞行力学》 CSCD 北大核心 2008年第1期40-43,共4页
设计了一种自适应飞行姿态控制器,在某一飞行条件下,建立了某型飞机的滚转通道动态逆模型,针对动态逆控制需要获得飞机精确数学模型的难点,基于B-Splines函数,构建了B-Splines网络,在线逼近模型逆误差,并根据李亚普诺夫能量函数推导了B-... 设计了一种自适应飞行姿态控制器,在某一飞行条件下,建立了某型飞机的滚转通道动态逆模型,针对动态逆控制需要获得飞机精确数学模型的难点,基于B-Splines函数,构建了B-Splines网络,在线逼近模型逆误差,并根据李亚普诺夫能量函数推导了B-Splines网络权值的更新算法,确保模型跟踪误差和网络权值的有界性。仿真结果表明,该控制器能够对模型逆误差快速自适应,系统对输入命令有较好的响应特性。 展开更多
关键词 动态逆 b-splines网络 姿态控制系统
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B-Spline曲线聚风装置直线翼垂直轴风力机启动性能数值模拟 被引量:2
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作者 李岩 马云飞 +2 位作者 佟国强 杨胜兵 肖振军 《排灌机械工程学报》 CSCD 北大核心 2024年第3期265-272,共8页
为了提升直线翼垂直轴风力机的启动性能,基于B-Spline曲线生成方法,提出一种具有流线型轮廓的聚风装置,将其分别安装在风轮顶端和底端,用以提升风轮附近的来流风速,使风轮汲取更多风能,达到更易启动的特点.选取聚风装置的5个结构参数进... 为了提升直线翼垂直轴风力机的启动性能,基于B-Spline曲线生成方法,提出一种具有流线型轮廓的聚风装置,将其分别安装在风轮顶端和底端,用以提升风轮附近的来流风速,使风轮汲取更多风能,达到更易启动的特点.选取聚风装置的5个结构参数进行设计:聚风装置与风轮间隙距离ΔL、底圆半径R_(1)、顶圆半径R_(2)、入口角度α_(1)和出口角度α_(2).设计方法采用二次旋转正交组合筛选最优模型,通过三维数值模拟研究聚风装置参数对直线翼垂直轴风力机启动性能的影响,获得了最佳外形参数组合.此外,对有无加装聚风装置的直线翼垂直轴风力机进行了静态三维数值模拟.结果表明,通过添加具有外凸流线型轮廓的聚风装置,直线翼垂直轴风力机的启动性能有显著提升.在风速较低的情况下,性能改善更加明显.聚风装置可使直线翼垂直轴风力机的平均启动力矩系数最大增加38.8%,峰值平均启动力矩系数最大可增加31.2%. 展开更多
关键词 垂直轴风力机 聚风装置 b-spline曲线 启动性能 数值模拟
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基于二维B-splines方法研究强磁场中类氢离子He+的低能能级
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作者 刘凤丽 《黑龙江大学自然科学学报》 2023年第5期596-604,共9页
采用改进的二维B-spline方法在柱坐标系下研究了强磁场下类氢离子He^(+)的结构和电子空间几率密度,计算包含三种对称性0^(+)、0^(-)和(^(-)1)^(+)共10个本征态1 0^(+)、2 0^(+)、ν 0^(-)(ν=1~4)和ν(-1)^(+)(ν=1~4)的能级,选定磁感... 采用改进的二维B-spline方法在柱坐标系下研究了强磁场下类氢离子He^(+)的结构和电子空间几率密度,计算包含三种对称性0^(+)、0^(-)和(^(-)1)^(+)共10个本征态1 0^(+)、2 0^(+)、ν 0^(-)(ν=1~4)和ν(-1)^(+)(ν=1~4)的能级,选定磁感应强度分别为0、0.001、0.003、0.005、0.007、0.010、0.030、0.050、0.070、0.100、0.200、0.300、0.500、0.700和1.000 a.u.。计算结果表明,类氢离子He^(+)的能级在强磁场中发生劈裂,简并度消除,得到了各个能级随磁感应强度变化规律,并且发现随着磁感应强度的增加能级高低会改变,甚至会发生能级翻转现象;定量地研究了类氢离子He^(+)的基态1 0^(+)和激发态3 0^(-)几率密度分布随磁感应强度的变化规律,并与氢原子进行比较。本研究部分计算结果与他人研究结果十分吻合,有助于进一步理解其他复杂原子的电子运动行为。 展开更多
关键词 b-spline方法 类氢离子He+ 强磁场 能级
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