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基于多表示动态自适应的不同工况下滚动轴承故障诊断
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作者 朱继扬 孙虎儿 +2 位作者 张天源 赵扬 白晓艺 《机电工程》 CAS 北大核心 2023年第2期178-185,203,共9页
在对不同工况下的滚动轴承进行故障诊断时,要收集足够多标记的故障样本是非常困难的。为此,以原始振动信号作为神经网络的输入,通过多表示动态自适应(MRDA)算法多表示对齐可迁移的特征、自适应动态的衡量边缘分布和条件分布相对重要性,... 在对不同工况下的滚动轴承进行故障诊断时,要收集足够多标记的故障样本是非常困难的。为此,以原始振动信号作为神经网络的输入,通过多表示动态自适应(MRDA)算法多表示对齐可迁移的特征、自适应动态的衡量边缘分布和条件分布相对重要性,从而构建了一种新的深度迁移模型,即一维多表示空洞动态自适应迁移网络(1D MRDDATN)。首先,对迁移学习数据分布进行了问题分析,对DDA进行了理论推导;然后,在一维空洞卷积基础上,创建了一维多表示空洞卷积神经网络(1D MRDCNN),并提出了MRDA算法和多表示动态自适应结构(MRDAM),形成了一维多表示空洞动态自适应迁移网络(1D MRDDATN);最后,采用美国凯斯西储大学(CWRU)的滚动轴承数据集进行了实验验证。研究结果表明:与传统的深度迁移学习方法相比,上述方法的平均诊断准确率有所提升,可达到98%以上;MRDA通过多表示对齐来完成不同工况下的跨域分类任务,自适应地捕获不同方面的信息,可以获得更好的性能。 展开更多
关键词 不同工况 一维多表示空洞动态自适应迁移网络 故障样本 深度迁移学习 多表示动态自适应算法 神经网络 一维多表示空洞卷积神经网络
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平行系统的人工环境构建技术 被引量:12
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作者 郭刚 陈彬 邱晓刚 《系统仿真学报》 CAS CSCD 北大核心 2011年第8期1686-1690,共5页
人工环境是平行系统的重要组成,特别是人工社会、智能模型、计算实验的基础支持。通过数据、模型描述和表示真实环境,通过传感和信息网络和动态演化逼近真实环境,通过高性能并行计算和接口标准为人工社会、计算实验和平行执行提供动态... 人工环境是平行系统的重要组成,特别是人工社会、智能模型、计算实验的基础支持。通过数据、模型描述和表示真实环境,通过传感和信息网络和动态演化逼近真实环境,通过高性能并行计算和接口标准为人工社会、计算实验和平行执行提供动态、准确、可信的环境信息和计算支持,是人工环境最本质的技术内涵。以数据和模型为中心,以并行计算技术和设施为支撑,通过传感器网络和信息网络进行动态演化,是构建人工环境的基础、有效方法。通过分析,指出人工环境构建的关键技术包括多表示/多分辨率技术、基于模型的动态环境技术、多源数据驱动的演化技术、高性能并行计算技术,同时提出了相应的技术思路和方案。 展开更多
关键词 平行系统 人工环境 多表示 多分辨率 演化 计算实验
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Multipartite State Representations in Multi-mode Fock Space and Their Squeezing Transformations 被引量:1
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作者 YUAN Hong-Chun LI Heng-Mei QI Kai-Guo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期31-34,共4页
We present the continuous state vector of the total coordinate of multi-partlcle and the state vector of their total momentum, respectively, which possess completeness relation in multi-mode Fock space by virtue of th... We present the continuous state vector of the total coordinate of multi-partlcle and the state vector of their total momentum, respectively, which possess completeness relation in multi-mode Fock space by virtue of the integration within an order product (IWOP) technique. We also calculate the transition from classical transformation of variables in the states to quantum unitary operator, deduce a new multi-mode squeezing operator, and discuss its squeezing effect. In progress, it indicates that the IWOP technique provides a convenient way to construct new representation in quantum mechanics. 展开更多
关键词 IWOP technique multipartite state representations squeezing operator
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Solving Dirac Equation with New Ring-Shaped Non-Spherical Harmonic Oscillator Potential 被引量:2
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作者 胡先权 罗光 +2 位作者 毋志民 牛连斌 马燕 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期242-246,共5页
A new ring-shaped non-harmonic oscillator potential is proposed. The precise bound solution of Dirac equation with the potential is gained when the scalar potential is equal to the vector potential. The angular equati... A new ring-shaped non-harmonic oscillator potential is proposed. The precise bound solution of Dirac equation with the potential is gained when the scalar potential is equal to the vector potential. The angular equation and radial equation are obtained through the variable separation method. The results indicate that the normalized angle wave function can be expressed with the generalized associated-Legendre polynomial, and the normalized radial wave function can be expressed with confluent hypergeometric function. And then the precise energy spectrum equations are obtained. The ground state and several low excited states of the system are solved. And those results are compared with the non-relativistic effect energy level in Phys. Lett. A 340 (2005) 94. The positive energy states of system are discussed and the conclusions are made properly. 展开更多
关键词 ring-shaped non-harmonic oscillator potential Dirac equation bound state generalizedassoeiated-Legendre function
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On Symplectic and Multisymplectic Structures and Their Discrete Versions in Lagrangian Formalism 被引量:4
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作者 GUOHan-Ying LIYu-Qi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第6期703-710,共8页
We introduce the Euler-Lagrange cohomology to study the symplectic and multisymplectic structures and their preserving properties in finite and infinite dimensional Lagrangian systems respectively. We also explore the... We introduce the Euler-Lagrange cohomology to study the symplectic and multisymplectic structures and their preserving properties in finite and infinite dimensional Lagrangian systems respectively. We also explore their certain difference discrete counterparts in the relevant regularly discretized finite and infinite dimensional Lagrangian systems by means of the difference discrete variational principle with the difference being regarded as an entire geometric object and the noncommutative differential calculus on regular lattice. In order to show that in all these cases the symplectic and multisymplectic preserving properties do not necessarily depend on the relevant Euler-Lagrange equations, the Euler-Lagrange cohomological concepts and content in the configuration space are employed. 展开更多
关键词 Euler-Lagrange cohomology difference discrete variational principle symplectic structure
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On Univalent Functions in Multiply Connected Domains
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作者 杨维奇 《Journal of Beijing Institute of Technology》 EI CAS 1994年第2期99-113,共15页
The present article is an account of results on univalent functions in multiply connected domains obtained by the author. It contains two rery simple proofs of Villat's formula; Schwarz's formula, Poisson'... The present article is an account of results on univalent functions in multiply connected domains obtained by the author. It contains two rery simple proofs of Villat's formula; Schwarz's formula, Poisson's formula and Poisson-Jensen formula in multiply connected domains; the differentiability theorem with respect to the parameter of analytic function family containing one parametric variable on multiply connected domains; variation theorem and parametric representation theorem of univalent functions in multiply connected domains; the solution of an extremal problem of differentiable functionals. 展开更多
关键词 univalent functions integral representation variational methods/multiply connected domains parametric representation method extremal problem
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Generalized Bargmann Representation of Spin Coherent State 被引量:1
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作者 FANHong-Yi CHENJun-Hu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第4期537-540,共4页
Based on the conclusion that the generalized Bargmann representation of a two-mode Fock state is a two-variable Hermite polynomial function /Hong-Yi Fan and Jun-hua Chen,Phys.Lett.A303(2002)311] we derive the generali... Based on the conclusion that the generalized Bargmann representation of a two-mode Fock state is a two-variable Hermite polynomial function /Hong-Yi Fan and Jun-hua Chen,Phys.Lett.A303(2002)311] we derive the generalized Bargmann representation of the spin coherent state and some new relations in the generalized function space. 展开更多
关键词 spin coherent state generalized Bargmann representation Hermite polynomials
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Construction of Odd-Variable Boolean Function with Maximum Algebraic Immunity Using Univariate Polynomial Representation
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作者 Zhao Wentao Fu Shaojing +1 位作者 Li Chao Qu Longjiang 《China Communications》 SCIE CSCD 2012年第10期33-39,共7页
To protect against algebraic attacks, a high algebraic immunity is now an important criterion for Boolean functions used in stream ciphers. In this paper, a new method based on a univariate polynomial representation o... To protect against algebraic attacks, a high algebraic immunity is now an important criterion for Boolean functions used in stream ciphers. In this paper, a new method based on a univariate polynomial representation of Boolean functions is proposed. The proposed method is used to constmct Boolean functions with an odd number of variables and with maximum algebraic immunity. We also discuss the nonlinearity of the constructed functions. Moreover, a lower bound is deter- mined for the number of Boolean functions with rmximum algebraic immunity. 展开更多
关键词 CRYPTOGRAPHY boolean function alge- braic attack algebraic immunity
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Construction and diversity analysis of a murine IgEphage surface display library
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作者 LIZONGDONG MINGYEH 《Cell Research》 SCIE CAS CSCD 1997年第2期161-170,共10页
To make further investigation of the IgE antibodyrepertoire in Trichosanthin (TCS) allergic responses, amurine IgE phage surface display library was constructed(3.0×105 independent clones). We first constructed t... To make further investigation of the IgE antibodyrepertoire in Trichosanthin (TCS) allergic responses, amurine IgE phage surface display library was constructed(3.0×105 independent clones). We first constructed theVe cDNA library (4.6×105 independent clones) and VκcDNA library (3.0×105 independent clones). Then, theVε and Vκ gene segments were amplified from both libraries by PCR respectively, and assembled into Fab fragment by SOE PCR. The phage library containing Fabs wasthus constructed. The diversity of Vε from this library wasanalyzed and proved. Fab clones with high specificity toTCS have been screened out. 展开更多
关键词 Phage surface display library trichosanthin murine IgE antibody
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A Note on Special Functions Related to Lotka / Negative Volterra Equations
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作者 Takashi Fujiwara 《Journal of Mathematics and System Science》 2017年第7期186-197,共12页
We study special functions related to Lotka-Volterra equations and negative Volterra equation intro-duced from zero curvature representations . At first we show the relationships between Lotka-Volterra equations intro... We study special functions related to Lotka-Volterra equations and negative Volterra equation intro-duced from zero curvature representations . At first we show the relationships between Lotka-Volterra equations introduced from zero curvature representations and symmetric orthogonal polynomials. Sec-ondarily, we describe the relationships between negative Volterra equations with a special solutions and cylinder functions. 展开更多
关键词 Lotka-Volterra equations Negative Volterra equations symmetric orthogonal polynomials cylinder functions three term recurrences
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Schematic interface of sound creation for computer animators
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作者 TONG Kam-pang Maya WONG Kam-wah 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第7期1141-1151,共11页
As an audiovisual medium, computer animations require superior image quality and professional soundtrack to lead audiences into their fascinating virtual world. Without sound, the impact of storytelling is reduced or ... As an audiovisual medium, computer animations require superior image quality and professional soundtrack to lead audiences into their fascinating virtual world. Without sound, the impact of storytelling is reduced or the story is even not under- standable. Despite the importance of sound, most animators are unfamiliar with sound editing software. Limited budget projects such as independent or student works have difficulty hiring sound professionals to create tailor-made soundtrack. Therefore, we need a suitable sound tool to express their individual ideas. In this paper, we propose an approach using schematic for both computer animation and sound. Our approach provides (1) physical simulation on sound through animation parameters and (2) a new channel for animators to add aesthetic values in sound through their experience of using schematics in existing animation software. We demonstrate our idea through several examples, such as Doppler shift, obstacle effect, importance, energetic, and sputtering effect. 展开更多
关键词 Computer animation MULTIMEDIA Digital media Schematics Physical simulation AESTHETIC Sound effects Soundtrack
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Entanglement Involved in Pair Coherent State Studied via Wigner Function Formalism
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作者 HU Li-Yun FAN Hong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第12期1071-1075,共5页
We calculate Wigner function, tomogram of the pair coherent state by using its Sehmidt decomposition in the coherent state representation. It turns out that the Wigner function can be seen as the quantum entanglement ... We calculate Wigner function, tomogram of the pair coherent state by using its Sehmidt decomposition in the coherent state representation. It turns out that the Wigner function can be seen as the quantum entanglement (QE) between two two-variable Hermite polynomials (TVHP) and the tomogram is further simplified as QE of two single-variable Hermite polynomials. The Husimi function of pair coherent state is also calculated. 展开更多
关键词 pair coherent state Wigner function TOMOGRAM Husimi function
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Computing polynomial univariate representations of zero-dimensional ideals by Grbner basis 被引量:3
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作者 MA XiaoDong SUN Yao WANG DingKang 《Science China Mathematics》 SCIE 2012年第6期1293-1302,共10页
Rational Univariate Representation (RUR) of zero-dimensional ideals is used to describe the zeros of zero-dimensional ideals and RUR has been studied extensively. In 1999, Roullier proposed an efficient algorithm to... Rational Univariate Representation (RUR) of zero-dimensional ideals is used to describe the zeros of zero-dimensional ideals and RUR has been studied extensively. In 1999, Roullier proposed an efficient algorithm to compute RUR of zero-dimensional ideals. In this paper, we will present a new algorithm to compute Polynomial Univariate Representation (PUR) of zero-dimensional ideals. The new algorithm is based on some interesting properties of Grobner basis. The new algorithm also provides a method for testing separating elements. 展开更多
关键词 RUR PUR zero-dimensional ideals Grobner basis
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Stable homotopy classification of A_n^4-polyhedra with 2-torsion free homology 被引量:1
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作者 PAN JianZhong ZHU ZhongJian 《Science China Mathematics》 SCIE CSCD 2016年第6期1141-1162,共22页
We study the stable homotopy types of F_n^4(2)-polyhedra, i.e.,(n- 1)-connected, at most(n+ 4)-dimensional polyhedra with 2-torsion free homologies. We are able to classify the indecomposable F_n^4(2)-polyhedra. The p... We study the stable homotopy types of F_n^4(2)-polyhedra, i.e.,(n- 1)-connected, at most(n+ 4)-dimensional polyhedra with 2-torsion free homologies. We are able to classify the indecomposable F_n^4(2)-polyhedra. The proof relies on the matrix problem technique which was developed in the classification of representations of algebras and applied to homotopy theory by Baues and Drozd(1999, 2001, 2004). 展开更多
关键词 HOMOTOPY INDECOMPOSABLE matrix problem
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A modified simulated annealing algorithm and an excessive area model for floorplanning using fixed-outline constraints 被引量:4
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作者 De-xuan ZOU Gai-ge WANG +1 位作者 Gai PAN Hong-wei QI 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第11期1228-1244,共17页
Outline-free floorplanning focuses on area and wirelength reductions, which are usually meaningless, since they can hardly satisfy modern design requirements. We concentrate on a more difficult and useful issue, fixed... Outline-free floorplanning focuses on area and wirelength reductions, which are usually meaningless, since they can hardly satisfy modern design requirements. We concentrate on a more difficult and useful issue, fixed-outline floorplanning. This issue imposes fixed-outline constraints on the outline-free floorplanning, making the physical design more interesting and challenging. The contributions of this paper are primarily twofold. First, a modified simulated annealing(MSA) algorithm is proposed. In the beginning of the evolutionary process, a new attenuation formula is used to decrease the temperature slowly, to enhance MSA's global searching capacity. After a period of time, the traditional attenuation formula is employed to decrease the temperature rapidly, to maintain MSA's local searching capacity. Second, an excessive area model is designed to guide MSA to find feasible solutions readily. This can save much time for refining feasible solutions. Additionally, B*-tree representation is known as a very useful method for characterizing floorplanning. Therefore, it is employed to perform a perturbing operation for MSA. Finally, six groups of benchmark instances with different dead spaces and aspect ratios—circuits n10, n30, n50, n100, n200, and n300—are chosen to demonstrate the efficiency of our proposed method on fixed-outline floorplanning. Compared to several existing methods, the proposed method is more efficient in obtaining desirable objective function values associated with the chip area, wirelength, and fixed-outline constraints. 展开更多
关键词 Fixed-outline floorplanning Modified simulated annealing algorithm Global search Excessive area model B*-tree representation
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Sharp Distortion Theorems for a Subclass of Biholomorphic Mappings Which Have a Parametric Representation in Several Complex Variables 被引量:2
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作者 Xiaosong LIU Taishun LIU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2016年第4期553-570,共18页
In this paper, the sharp distortion theorems of the Frechet-derivative type for a subclass of biholomorphic mappings which have a parametric representation on the unit ball of complex Banach spaces are established, an... In this paper, the sharp distortion theorems of the Frechet-derivative type for a subclass of biholomorphic mappings which have a parametric representation on the unit ball of complex Banach spaces are established, and the corresponding results of the above generalized mappings on the unit polydisk in Cn are also given. Meanwhile, the sharp distortion theorems of the Jacobi determinant type for a subclass of biholomorphic mappings which have a parametric representation on the unit ball with an arbitrary norm in C~ are obtained, and the corresponding results of the above generalized mappings on the unit polydisk in C~ are got as well. Thus, some known results in prior literatures are generalized. 展开更多
关键词 Distortion theorem A zero of order k 1 Frechet-derivative Jacobideterminant Parametric representation
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An algorithm for computing the factor ring of an ideal in a Dedekind domain with finite rank
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作者 Dandan Huang Yingpu Deng 《Science China Mathematics》 SCIE CSCD 2018年第5期783-796,共14页
We give an algorithm for computing the factor ring of a given ideal in a Dedekind domain with finite rank, which runs in deterministic and polynomial time. We provide two applications of the algorithm:judging whether ... We give an algorithm for computing the factor ring of a given ideal in a Dedekind domain with finite rank, which runs in deterministic and polynomial time. We provide two applications of the algorithm:judging whether a given ideal is prime or prime power. The main algorithm is based on basis representation of finite rings which is computed via Hermite and Smith normal forms. 展开更多
关键词 deterministic polynomial-time test Dedekind domains basis representation Hermite and Smith normal forms
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Nonparametric estimation of quantiles for a class of stationary processes
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作者 HUANG Chu WANG HanChao LIN ZhengYan 《Science China Mathematics》 SCIE CSCD 2015年第12期2621-2632,共12页
We study smoothed quantile estimator for a class of stationary processes. We obtain the convergency rates and the Bahadur representation, as well as the asymptotic normality for this estimator by the method of m-depen... We study smoothed quantile estimator for a class of stationary processes. We obtain the convergency rates and the Bahadur representation, as well as the asymptotic normality for this estimator by the method of m-dependent approximation. Our results can be used in the study of the estimation of value-at-risk(Va R) and applied to many time series which have important applications in econometrics. 展开更多
关键词 quantile estimator kernel method causal process m-dependent approximation asymptotic inference
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