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MULTIPLICITY OF NORMALIZED SOLUTIONS FOR THE FRACTIONAL SCHR?DINGER-POISSON SYSTEM WITH DOUBLY CRITICAL GROWTH
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作者 孟禹希 贺小明 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期997-1019,共23页
In this paper,we are concerned with solutions to the fractional Schrodinger-Poisson system■ with prescribed mass ∫_(R^(3))|u|^(2)dx=a^(2),where a> 0 is a prescribed number,μ> 0 is a paremeter,s ∈(0,1),2 <... In this paper,we are concerned with solutions to the fractional Schrodinger-Poisson system■ with prescribed mass ∫_(R^(3))|u|^(2)dx=a^(2),where a> 0 is a prescribed number,μ> 0 is a paremeter,s ∈(0,1),2 <q <2_(s)^(*),and 2_(s)^(*)=6/(3-2s) is the fractional critical Sobolev exponent.In the L2-subcritical case,we show the existence of multiple normalized solutions by using the genus theory and the truncation technique;in the L^(2)-supercritical case,we obtain a couple of normalized solutions by developing a fiber map.Under both cases,to recover the loss of compactness of the energy functional caused by the doubly critical growth,we need to adopt the concentration-compactness principle.Our results complement and improve upon some existing studies on the fractional Schrodinger-Poisson system with a nonlocal critical term. 展开更多
关键词 fractional Schrodinger-Poisson system normalized solutions variational methods L^(2)-subcritical L^(2)-supercritical
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Normalized Ground State Solutions of Nonlinear Choquard Equations with Nonconstant Potential
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作者 LI Nan ZHAO Hui-yan XU Li-ping 《Chinese Quarterly Journal of Mathematics》 2024年第3期250-261,共12页
In this paper,we mainly focus on the following Choquard equation-{△u-V(x)(I_(a*)|u|^(p))|u|^(p-2)u=λu,x∈R^(N),u∈H^(1)(R^(N))where N≥1,λ∈R will arise as a Lagrange multiplier,0<a<N and N+a/N<p<N+a+2/... In this paper,we mainly focus on the following Choquard equation-{△u-V(x)(I_(a*)|u|^(p))|u|^(p-2)u=λu,x∈R^(N),u∈H^(1)(R^(N))where N≥1,λ∈R will arise as a Lagrange multiplier,0<a<N and N+a/N<p<N+a+2/N Under appropriate hypotheses on V(x),we prove that the above Choquard equation has a normalized ground state solution by utilizing variational methods. 展开更多
关键词 Choquard equation Nonconstant potential function normalized ground state solutions Variational methods
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Three-dimensional color particle image velocimetry based on a cross-correlation and optical flow method
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作者 单良 熊俊哲 +4 位作者 施飞杨 洪波 简娟 詹虹晖 孔明 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期88-96,共9页
Rainbow particle image velocimetry(PIV)can restore the three-dimensional velocity field of particles with a single camera;however,it requires a relatively long time to complete the reconstruction.This paper proposes a... Rainbow particle image velocimetry(PIV)can restore the three-dimensional velocity field of particles with a single camera;however,it requires a relatively long time to complete the reconstruction.This paper proposes a hybrid algorithm that combines the fast Fourier transform(FFT)based co-correlation algorithm and the Horn–Schunck(HS)optical flow pyramid iterative algorithm to increase the reconstruction speed.The Rankine vortex simulation experiment was performed,in which the particle velocity field was reconstructed using the proposed algorithm and the rainbow PIV method.The average endpoint error and average angular error of the proposed algorithm were roughly the same as those of the rainbow PIV algorithm;nevertheless,the reconstruction time was 20%shorter.Furthermore,the effect of velocity magnitude and particle density on the reconstruction results was analyzed.In the end,the performance of the proposed algorithm was verified using real experimental single-vortex and double-vortex datasets,from which a similar particle velocity field was obtained compared with the rainbow PIV algorithm.The results show that the reconstruction speed of the proposed hybrid algorithm is approximately 25%faster than that of the rainbow PIV algorithm. 展开更多
关键词 particle image velocimetry color light cross-correlation and optical flow method VORTEX
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New normalized nonlocal hybrid level set method for image segmentation 被引量:1
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作者 LOU Qiong PENG Jia-lin +1 位作者 KONG De-xing WANG Chun-lin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第4期407-421,共15页
This article introduces a new normalized nonlocal hybrid level set method for image segmentation.Due to intensity overlapping,blurred edges with complex backgrounds,simple intensity and texture information,such kind o... This article introduces a new normalized nonlocal hybrid level set method for image segmentation.Due to intensity overlapping,blurred edges with complex backgrounds,simple intensity and texture information,such kind of image segmentation is still a challenging task.The proposed method uses both the region and boundary information to achieve accurate segmentation results.The region information can help to identify rough region of interest and prevent the boundary leakage problem.It makes use of normalized nonlocal comparisons between pairs of patches in each region,and a heuristic intensity model is proposed to suppress irrelevant strong edges and constrain the segmentation.The boundary information can help to detect the precise location of the target object,it makes use of the geodesic active contour model to obtain the target boundary.The corresponding variational segmentation problem is implemented by a level set formulation.We use an internal energy term for geometric active contours to penalize the deviation of the level set function from a signed distance function.At last,experimental results on synthetic images and real images are shown in the paper with promising results. 展开更多
关键词 image segmentation level set method nonlocal method intensity information active contours normalIZATION
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Aggregation operators and CRITIC-VIKOR method for confidence complex q-rung orthopair normal fuzzy information and their applications
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作者 Tahir Mahmood Zeeshan Ali Muhammad Naeem 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第1期40-63,共24页
Supply chain management is an essential part of an organisation's sustainable programme.Understanding the concentration of natural environment,public,and economic influence and feasibility of your suppliers and pu... Supply chain management is an essential part of an organisation's sustainable programme.Understanding the concentration of natural environment,public,and economic influence and feasibility of your suppliers and purchasers is becoming progressively familiar as all industries are moving towards a massive sustainable potential.To handle such sort of developments in supply chain management the involvement of fuzzy settings and their generalisations is playing an important role.Keeping in mind this role,the aim of this study is to analyse the role and involvement of complex q-rung orthopair normal fuzzy(CQRONF)information in supply chain management.The major impact of this theory is to analyse the notion of confidence CQRONF weighted averaging,confidence CQRONF ordered weighted averaging,confidence CQRONF hybrid averaging,confidence CQRONF weighted geometric,confidence CQRONF ordered weighted geometric,confidence CQRONF hybrid geometric operators and try to diagnose various properties and results.Furthermore,with the help of the CRITIC and VIKOR models,we diagnosed the novel theory of the CQRONF-CRITIC-VIKOR model to check the sensitivity analysis of the initiated method.Moreover,in the availability of diagnosed operators,we constructed a multi-attribute decision-making tool for finding a beneficial sustainable supplier to handle complex dilemmas.Finally,the initiated operator's efficiency is proved by comparative analysis. 展开更多
关键词 averaging/geometric aggregation operators complex q-rung orthopair normal fuzzy information confidence levels strategic decision-making methods
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First-Arrival Picking Method for Active Source Data with Ocean Bottom Seismometers Based on Spatial Waveform Variation Characteristics
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作者 LIU Hongwei XING Lei +3 位作者 ZHU Henghua ZHANG Jin ZHANG Jing LIU Huaishan 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期970-980,共11页
The precision and reliability of first-arrival picking are crucial for determining the accuracy of geological structure inversion using active source ocean bottom seismometer(OBS)refraction data.Traditional methods fo... The precision and reliability of first-arrival picking are crucial for determining the accuracy of geological structure inversion using active source ocean bottom seismometer(OBS)refraction data.Traditional methods for first-arrival picking based on sample points are characterized by theoretical errors,especially in low-sampling-frequency OBS data because the travel time of seismic waves is not an integer multiple of the sampling interval.In this paper,a first-arrival picking method that utilizes the spatial waveform variation characteristics of active source OBS data is presented.First,the distribution law of theoretical error is examined;adjacent traces exhibit variation characteristics in their waveforms.Second,a label cross-correlation superposition method for extracting highfrequency signals is presented to enhance the first-arrival picking precision.Results from synthetic and field data verify that the proposed approach is robust,successfully overcomes the limitations of low sampling frequency,and achieves precise outcomes that are comparable with those of high-sampling-frequency data. 展开更多
关键词 first-arrival picking spatial waveform variation label cross-correlation superposition method
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结合小波系数的normalized cut分割算法 被引量:1
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作者 黄颖 杨光琼 《计算机应用》 CSCD 北大核心 2011年第1期182-183,242,共3页
为了提高normalized cut分割算法的准确率,结合小波系数调整图像的亲和矩阵。首先采用小波系数计算图像的边缘信息,然后使用边缘信息对原始图像构造一个图,求取图的拉普拉斯矩阵的前K个特征值,并对第二个特征值对应的特征向量进行分类,... 为了提高normalized cut分割算法的准确率,结合小波系数调整图像的亲和矩阵。首先采用小波系数计算图像的边缘信息,然后使用边缘信息对原始图像构造一个图,求取图的拉普拉斯矩阵的前K个特征值,并对第二个特征值对应的特征向量进行分类,得到最终的分割结果。使用一些自然图像进行了验证,结果证明新方法能提取目标更为细致的细节,保留更多有用的信息。 展开更多
关键词 图像分割 normalized cut方法 小波系数 图分割
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基于图论的Normalized Cut图像分割方法研究 被引量:6
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作者 杨宇鹏 赵卫东 +1 位作者 王志成 陈刚 《计算机与现代化》 2010年第1期113-116,共4页
基于图论的图像分割是近年来国际上研究图像分割算法领域中一个新的热点研究方向,Normalized Cut(规一化分割)是基于图论的分割方法中比较典型的一种。本文介绍Normalized Cut方法的相关内容,分析它的优缺点并提出几种有效的改进方法。... 基于图论的图像分割是近年来国际上研究图像分割算法领域中一个新的热点研究方向,Normalized Cut(规一化分割)是基于图论的分割方法中比较典型的一种。本文介绍Normalized Cut方法的相关内容,分析它的优缺点并提出几种有效的改进方法。最后,实验显示Normalized Cut在特定图片的分割上取得了不错的效果。 展开更多
关键词 图像分割 图论 规一化分割 NYSTROM方法
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Grey Clustering Evaluation on Regional Eco-environmental Quality Based on Normalized Index Value 被引量:7
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作者 TIAN Wen-xin, LI Zuo-yong, LIU Wei, YU Chun-xue College of Resources and Environmental Sciences, Chengdu University of Information Technology, Chengdu 610225, China 《Meteorological and Environmental Research》 CAS 2011年第4期65-67,71,共4页
[Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey cl... [Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey clustering method based on normalized index value, and the evaluation results were compared with those of unascertained measure method to verify the feasibility of grey clustering method used to evaluate regional eco-environmental quality. [Result] In the grey clustering assessment method based on normalized index value, indices whose standard normalized values in the same grade were close to each other were classified into one class and had the same whitening function, which reduced the number of whitening functions. Grey clustering method based on normalized index value was used to assess eco-environmental quality in Chaohu basin, and the evaluation results were basically in accordance with those of unascertained measure method, namely eco-environmental quality in Hefei, Chaohu and Lu’an belonged to the third (pass), fourth (worse) and fifth grade (bad), except for one grade difference in overall basin, and the results showed that the method had practicality and could be applied to assess regional eco-environmental quality. [Conclusion] The study could provide theoretical foundation for the establishment of comprehensive management countermeasures of regional ecological environment. 展开更多
关键词 normalIZATION Gray clustering method Eco-environment quality evaluation Chaohu basin China
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A NEW MOMENT METHOD FOR THE FAST AND ACCURATE ANALYSIS OF NORMAL MODE HELICAL ANTENNAS 被引量:2
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作者 Ji Yicai Sun Baohua Liu Qizhong (Institute of Antennas and EM Scattering, Xidian University, Xi’an 710071) 《Journal of Electronics(China)》 2001年第4期355-358,共4页
In this letter, a new moment method using helical segments is presented to model Normal Mode Helical Antenna (NMHA). Using this method, the NMHA can be modeled by a few segments. The current distributions and radiatio... In this letter, a new moment method using helical segments is presented to model Normal Mode Helical Antenna (NMHA). Using this method, the NMHA can be modeled by a few segments. The current distributions and radiation patterns of some NMHAs are calculated.A comparison is made between results obtained using this helical segment algorithm and a linear segment algorithm, and the results of the two algorithms agree fairly well. When calculating the impedance matrix [Z], all the elements of the matrix can be obtained by only calculating a few elements with the application of the symmetric and periodic characteristics of the NMHA.Therefore, the CPU time and the memory storage are significantly reduced, with the accuracy and speed enhanced. 展开更多
关键词 MOMENT method HELICAL SEGMENT normal MODE HELICAL ANTENNA (NMHA)
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Applying invariant eigen-operator method to deriving normal coordinates of general classical Hamiltonian 被引量:1
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作者 范洪义 陈俊华 袁洪春 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期145-149,共5页
For classical Hamiltonian with general form H = 1/2∑ijMijpipj+1/2∑ijLijqiqj we find a new convenient way to obtain its normal coordinates, namely, let H be quantised and then employ the invariant eigen-operator (... For classical Hamiltonian with general form H = 1/2∑ijMijpipj+1/2∑ijLijqiqj we find a new convenient way to obtain its normal coordinates, namely, let H be quantised and then employ the invariant eigen-operator (IEO) method (Fan et al. 2004 Phys. Lett. A 321 75) to derive them. The general matrix equation, which relies on M and L, for obtaining the normal coordinates of H is derived. 展开更多
关键词 invariant eigen-operator method method normal coordinates
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Dombi-Normalized Weighted Bonferroni Mean Operators with Novel Multiple-Valued Complex Neutrosophic Uncertain Linguistic Sets and Their Application in Decision Making 被引量:1
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作者 Tahir Mahmood Zeeshan Ali +1 位作者 Dulyawit Prangchumpol Thammarat Panityakul 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第3期1587-1623,共37页
Although fuzzy set concepts have evolved,neutrosophic sets are attractingmore attention due to the greater power of the structure of neutrosophic sets.The ability to account for components that are true,false or neith... Although fuzzy set concepts have evolved,neutrosophic sets are attractingmore attention due to the greater power of the structure of neutrosophic sets.The ability to account for components that are true,false or neither true nor false is useful in the resolution of real-life problems.However,simultaneous variations render neutrosophic sets unsuitable in specific circumstances.To enable the management of these sorts of issues,we combine the principle of multi-valued neutrosophic uncertain linguistic sets and complex fuzzy sets to develop the principle of multivalued complex neutrosophic uncertain linguistic sets.Multi-valued complex neutrosophic uncertain linguistic sets can contain grades of truth,abstinence,and falsity,and uncertain linguistic terms,which are expressed as complex numbers whose real and imaginary parts are limited to the unit interval.Some important Dombi laws are elaborated along with Bonferroni mean operators,which offer a flexible general structure with modifiable factors.Bonferroni means aggregation operators perform a significant role in conveying the magnitude level of options and characteristics.To determine relationships among any number of attributes,we develop multi-valued complex neutrosophic uncertain linguistic Dombi-normalized weighted Bonferroni mean operators and discuss their important properties with some special cases.By using these laws,we can deploy themulti-attribute decisionmaking(MADM)technique using the novel principle of multi-valued complex neutrosophic uncertain linguistic sets.To determine the power and flexibility of the elaborated approach,we resolve some numerical examples based on the proposed operator.Finally,the work is validated with the help of comparative analysis,a discussion of its advantages,and geometric expressions of the elaborated theories. 展开更多
关键词 Multi-valued complex neutrosophic uncertain linguistic sets Dombi normalized weighted Bonferroni mean operators multi-attribute decision-making methods
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COMPLEX INNER PRODUCT AVERAGING METHOD FOR CALCULATING NORMAL FORM OF ODE
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作者 CHEN Yu-shu(陈予恕) +1 位作者 SUN Hong-jun(孙洪军) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第12期1368-1374,共7页
This paper puts forward a complex inner product averaging method for calculating normal form of ODE. Compared with conventional averaging method, the theoretic analytical process has such simple forms as to realize co... This paper puts forward a complex inner product averaging method for calculating normal form of ODE. Compared with conventional averaging method, the theoretic analytical process has such simple forms as to realize computer program easily. Results can be applied in both autonomous and non-autonomous systems. At last, an example is resolved to verify the method. 展开更多
关键词 nonlinear dynamic system normal form complex inner product averaging method
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ADJOINT OPERATOR METHOD AND NORMAL FORMS OF HIGHER ORDER FOR NONLINEAR DYNAMICAL SYSTEM
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作者 张伟 陈予恕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第5期449-461,共13页
Normal form theory is a very effective method when we study degenerate bifurcations of nonlinear dynamical systems. In this paper by using adjoint operator method, normal forms of order 3 and 4 for nonlinear dynamical... Normal form theory is a very effective method when we study degenerate bifurcations of nonlinear dynamical systems. In this paper by using adjoint operator method, normal forms of order 3 and 4 for nonlinear dynamical system with nilpotent linear part and Z(2)-asymmetry are computed. According to normal forms obtained, universal unfoldings for some degenerate bifurcation cases of codimension 3 and simple global characterizations, are studied. 展开更多
关键词 nonlinear dynamical system adjoint operator method normal forms of order 3 and 4 degenerate bifurcation of codimension 3 universal unfolding
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Stochastic resonance in a gain-noise model of a single-mode laser driven by pump noise and quantum noise with cross-correlation between real and imaginary parts under direct signal modulation
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作者 陈黎梅 曹力 吴大进 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第1期123-129,共7页
Stochastic resonance (SR) is studied in a gain-noise model of a single-mode laser driven by a coloured pump noise and a quantum noise with cross-correlation between real and imaginary parts under a direct signal mod... Stochastic resonance (SR) is studied in a gain-noise model of a single-mode laser driven by a coloured pump noise and a quantum noise with cross-correlation between real and imaginary parts under a direct signal modulation. By using a linear approximation method, we find that the SR appears during the variation of signal-to-noise ratio (SNR) separately with the pump noise self-correlation time τ, the noise correlation coefficient between the real part and the imaginary part of the quantum noise λq, the attenuation coefficient γ' and the deterministic steady-state intensity I0. In addition, it is found that the SR can be characterized not only by the dependence of SNR on the noise variables of and λq, but also by the dependence of SNR on the laser system variables of γ and I0. Thus our investigation extends the characteristic quantity of SR proposed before. 展开更多
关键词 stochastic resonance direct modulation signal quantum noise with cross-correlation between real and imaginary part linear approximation method
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Secrecy sum-rate analysis of massive MIMO systems under dual-threat attacks using normalization methods
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作者 Kishan Neupane Rami J.Haddad 《Digital Communications and Networks》 SCIE 2019年第4期237-244,共8页
Massive Multiple Input Multiple Output(MIMO)has been considered as an emerging technology to enhance the spectral and energy efficiency for the upcoming wireless communication systems.This paper derives a closedform a... Massive Multiple Input Multiple Output(MIMO)has been considered as an emerging technology to enhance the spectral and energy efficiency for the upcoming wireless communication systems.This paper derives a closedform approximation for the Ergodic Achievable Secrecy Sum-Rate(EASSR)by considering the joint impact of eavesdroppers and jammers.Two widely used linear precoding techniques,Zero-Forcing(ZF)and Maximum Ratio Transmission(MRT),were used in conjunction with matrix and vector normalization to analyze the secrecy performance.Closed-form expressions are used to explain how the secrecy performance is affected when using the ZF and MRT precoding in the eavesdropping and jamming attack models.We also analyze and compare the performances of different combinations of normalization method and precoding technique in various scenarios.From the analytical expressions and simulation results,we observe that the vector and matrix normalization perform better for the ZF precoding than for the MRT precoding in high Signal-to-Noise Ratio(SNR)scenarios.However,in low SNR,the MRT with matrix normalization outperforms the ZF with vector normalization regardless of the number of users in the system.Further,we observe that the MRT fails to serve more than two users in high SNR scenario.Numerical results obtained from Monte Carlo simulation are used to corroborate the accuracy of the asymptotic secrecy analysis. 展开更多
关键词 Massive MIMO Linear precoding normalization methods Secrecy analysis
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Finite element analysis on stresses field of normalized layer thickness within ceramic coating on aluminized steel
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作者 吴振强 夏原 +1 位作者 李光 徐方涛 《中国有色金属学会会刊:英文版》 EI CSCD 2007年第5期934-939,共6页
Multilayer ceramic coatings were fabricated on steel substrate using a combined technique of hot dipping aluminum(HDA) and plasma electrolytic oxidation(PEO). A triangle of normalized layer thickness was created for d... Multilayer ceramic coatings were fabricated on steel substrate using a combined technique of hot dipping aluminum(HDA) and plasma electrolytic oxidation(PEO). A triangle of normalized layer thickness was created for describing thickness ratios of HDA/PEO coatings. Then, the effect of thickness ratio on stresses field of HDA/PEO coatings subjected to uniform normal contact load was investigated by finite element method. Results show that the surface tensile stress is mainly affected by the thickness ratio of Al layer when the total thickness of coating is unchanged. With the increase of Al layer thickness, the surface tensile stress rises quickly. When Al2O3 layer thickness increases, surface tensile stress is diminished. Meanwhile, the maximum shear stress moves rapidly towards internal part of HDA/PEO coatings. Shear stress at the Al2O3 /Al interface is minimal when Al2O3 layer and Al layer have the same thickness. 展开更多
关键词 标准厚度 多层涂料 有限元方法 界面应力
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师范院校高等数学教学存在的问题与对策 被引量:2
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作者 李波 连颖颖 《教育理论与实践》 北大核心 2024年第3期52-55,共4页
高等数学是诸多师范专业必修的公共基础课,对于培养学生的专业学科素养和思维能力发挥着不可替代的作用。师范院校高等数学教学存在教学大纲一刀切,教学方法因循守旧,评价方式单一的问题,应对教学大纲进行优化调整,细化到每个学院的每... 高等数学是诸多师范专业必修的公共基础课,对于培养学生的专业学科素养和思维能力发挥着不可替代的作用。师范院校高等数学教学存在教学大纲一刀切,教学方法因循守旧,评价方式单一的问题,应对教学大纲进行优化调整,细化到每个学院的每个专业;改进教学方法,以线上线下的混合式教学模式代替单一的线下教学模式,同时将翻转课堂引进高数课堂;建立以专业为导向的多元、科学、有效的课程评价方式,以更大程度上促进高等数学课程目标的实现。 展开更多
关键词 师范院校 高等数学 教学改革 教学大纲 教学方法 教学模式 课程评价方式
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基于组合赋权与灰云模型的综合能源系统需求响应效益评价 被引量:2
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作者 盛四清 张佳欣 李然 《华北电力大学学报(自然科学版)》 CAS 北大核心 2024年第2期41-52,I0008,I0009,共14页
考虑到当前综合能源系统研究缺乏完善的需求响应量化评估方案,难以在优化运行层面综合评估需求响应效益这一问题,提出了一种基于改进AHP群决策—CRITIC组合赋权与灰云模型的综合能源系统需求响应效益评价方法。首先,从综合能效性、社会... 考虑到当前综合能源系统研究缺乏完善的需求响应量化评估方案,难以在优化运行层面综合评估需求响应效益这一问题,提出了一种基于改进AHP群决策—CRITIC组合赋权与灰云模型的综合能源系统需求响应效益评价方法。首先,从综合能效性、社会经济性和需求侧互动性三个维度构建了需求响应效益评价指标体系。其次,采用一致性和权重拟合性更优的指数标度法构造判断矩阵,降低赋值误差,并通过AHP群决策法确定主观权重,从而削弱主观极值偏差对权重的影响;在由CRITIC法确定客观权重后,基于最小欧氏距离建立组合权重模型,并通过非线性规划求取最优组合权重;针对评价等级信息的模糊性与隶属等级的随机性,采用正态灰云白化权模型确定指标分类等级与场景评分。最后,以北方某综合能源系统为例,根据用户参与需求响应方式设置了4种运行场景,分析了不同需求响应对系统运行的影响与作用,算例结果表明所提指标体系与评价方法科学有效。 展开更多
关键词 综合能源系统 需求侧响应 综合评价 AHP群决策法 CRITIC法 最小欧式距离 正态灰云白化权模型
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基于勒让德-扫描法的机械结合部法向接触刚度区间分析
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作者 刘勇 渠杰 +2 位作者 张青 王大伟 闫方超 《振动与冲击》 EI CSCD 北大核心 2024年第8期70-77,共8页
由于机械结合部实际接触时存在诸多不确定因素,利用传统接触刚度模型对机械结合部进行分析时,难以确定其法向接触刚度的合理区间。为此,将微凸体曲率半径、分布密度和微凸体高度方差视为不确定性参数,基于KE弹塑性接触刚度模型和勒让德... 由于机械结合部实际接触时存在诸多不确定因素,利用传统接触刚度模型对机械结合部进行分析时,难以确定其法向接触刚度的合理区间。为此,将微凸体曲率半径、分布密度和微凸体高度方差视为不确定性参数,基于KE弹塑性接触刚度模型和勒让德-扫描法,建立结合部法向接触刚度区间模型并进行求解。通过与接触刚度试验数据及传统模型求解结果的对比,验证了该模型的有效性和准确性。基于该模型对结合部法向接触刚度进行分析,结果表明:勒让德-扫描法具有较高的求解精度,粗糙表面形貌参数不确定性对于结合部法向接触刚度有着明显影响,且随着无量纲接触距离的减小,影响程度逐渐增加,其中微凸体高度方差的不确定性对粗糙表面法向接触刚度影响程度最大。机械结合部法向接触刚度区间模型的建立与分析,可为结合部的研究提供参考。 展开更多
关键词 航空发动机 不确定性 法向接触刚度 勒让德多项式 扫描法
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