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Symmetry Transformations and Exact Solutions of a Generalized Hyperelastic Rod Equation 被引量:1
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作者 Ran Wang Xuegang Yuan +2 位作者 Hongwu Zhang Jing Zhang Na Lv 《Computers, Materials & Continua》 SCIE EI 2018年第5期345-357,共13页
In this paper,a nonlinear wave equation with variable coefficients is studied,interestingly,this equation can be used to describe the travelling waves propagating along the circular rod composed of a general compressi... In this paper,a nonlinear wave equation with variable coefficients is studied,interestingly,this equation can be used to describe the travelling waves propagating along the circular rod composed of a general compressible hyperelastic material with variable cross-sections and variable material densities.With the aid of Lou’s direct method1,the nonlinear wave equation with variable coefficients is reduced and two sets of symmetry transformations and exact solutions of the nonlinear wave equation are obtained.The corresponding numerical examples of exact solutions are presented by using different coefficients.Particularly,while the variable coefficients are taken as some special constants,the nonlinear wave equation with variable coefficients reduces to the one with constant coefficients,which can be used to describe the propagation of the travelling waves in general cylindrical rods composed of generally hyperelastic materials.Using the same method to solve the nonlinear wave equation,the validity and rationality of this method are verified. 展开更多
关键词 generalized hyperelastic rod equation symmetry transformation Lou’s direct method exact solution
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Mutual transformations between the P–Q, Q–P, and generalized Weyl ordering of operators
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作者 徐兴磊 李洪奇 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期119-122,共4页
Based on the generalized Weyl quantization scheme, which relies on the generalized Wigner operator Ok (p, q) with a real k parameter and can unify the P-Q, Q-P, and Weyl ordering of operators in k = 1, - 1,0, respec... Based on the generalized Weyl quantization scheme, which relies on the generalized Wigner operator Ok (p, q) with a real k parameter and can unify the P-Q, Q-P, and Weyl ordering of operators in k = 1, - 1,0, respectively, we find the mutual transformations between 6 (p - P) (q - Q), (q - Q) 3 (p - P), and (p, q), which are, respectively, the integration kernels of the P-Q, Q-P, and generalized Weyl quantization schemes. The mutual transformations provide us with a new approach to deriving the Wigner function of quantum states. The - and - ordered forms of (p, q) are also derived, which helps us to put the operators into their - and - ordering, respectively. 展开更多
关键词 generalized Wigner operator generalized Weyl quantization scheme different operator orderingrules mutual transformation
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Generalized Canonical Transformations for Fractional Birkhoffian Systems
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作者 ZHANG Yi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第4期499-506,共8页
This paper presents fractional generalized canonical transformations for fractional Birkhoffian systems within Caputo derivatives.Firstly,based on fractional Pfaff-Birkhoff principle within Caputo derivatives,fraction... This paper presents fractional generalized canonical transformations for fractional Birkhoffian systems within Caputo derivatives.Firstly,based on fractional Pfaff-Birkhoff principle within Caputo derivatives,fractional Birkhoff’s equations are derived and the basic identity of constructing generalized canonical transformations is proposed.Secondly,according to the fact that the generating functions contain new and old variables,four kinds of generating functions of the fractional Birkhoffian system are proposed,and four basic forms of fractional generalized canonical transformations are deduced.Then,fractional canonical transformations for fractional Hamiltonian system are given.Some interesting examples are finally listed. 展开更多
关键词 fractional Birkhoffian system generalized canonical transformation fractional Pfaff-Birkhoff principle generating function
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Pseudopotentials,Lax Pairs and Bcklund Transformations for Generalized Fifth-Order KdV Equation
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作者 杨云青 陈勇 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第1期25-28,共4页
Based on the method developed by Nucci, the pseudopotentials, Lax pairs and the mngulanty mamtoia equations of the generalized fifth-order KdV equation are derived. By choosing different coefficient, the corresponding... Based on the method developed by Nucci, the pseudopotentials, Lax pairs and the mngulanty mamtoia equations of the generalized fifth-order KdV equation are derived. By choosing different coefficient, the corresponding results and the Backlund transformations can be obtained on three conditioners which include Caudrey-Dodd-Cibbon- Sawada-Kotera equation, the Lax equation and the Kaup-kupershmidt equation. 展开更多
关键词 generalized fifth-order KdV equation PSEUDOPOTENTIAL Lax pair Backlund transformation
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In the Atmosphere and Oceanic Fluids:Scaling Transformations,Bilinear Forms,Bäcklund Transformations and Solitons for A Generalized Variable-Coefficient Korteweg-de Vries-Modified Korteweg-de Vries Equation
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作者 GAO Xin-yi GUO Yong-jiang +3 位作者 SHAN Wen-rui ZHOU Tian-yu WANG Meng YANGDan-yu 《China Ocean Engineering》 SCIE EI CSCD 2021年第4期518-530,共13页
The atmosphere is an evolutionary agent essential to the shaping of a planet,while in oceanic science and daily life,liquids are commonly seen.In this paper,we investigate a generalized variable-coefficient Korteweg-d... The atmosphere is an evolutionary agent essential to the shaping of a planet,while in oceanic science and daily life,liquids are commonly seen.In this paper,we investigate a generalized variable-coefficient Korteweg-de Vriesmodified Korteweg-de Vries equation for the atmosphere,oceanic fluids and plasmas.With symbolic computation,beginning with a presumption,we work out certain scaling transformations,bilinear forms through the binary Bell polynomials and our scaling transformations,N solitons(with N being a positive integer)via the aforementioned bilinear forms and bilinear auto-Bäcklund transformations through the Hirota method with some solitons.In addition,Painlevé-type auto-Bäcklund transformations with some solitons are symbolically computed out.Respective dependences and constraints on the variable/constant coefficients are discussed,while those coefficients correspond to the quadratic-nonlinear,cubic-nonlinear,dispersive,dissipative and line-damping effects in the atmosphere,oceanic fluids and plasmas. 展开更多
关键词 atmosphere oceanic fluids plasmas generalized variable-coefficient Korteweg-de Vries-modified Korteweg-de Vries equation scaling transformations bilinear forms N solitons auto-Bäcklund transformations
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Linearization of Emden Differential Equation via the Generalized Sundman Transformations
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作者 Joel Mvendaga Orverem Yusuf Haruna +1 位作者 Bala Ma’aji Abdulhamid Magaji Yunbunga Adamu 《Advances in Pure Mathematics》 2021年第3期163-168,共6页
The Emden differential equation is one of the most widely studied and challenging nonlinear dynamics equations in literature. It finds applications in various areas of study such as celestial mechanics, fluid mechanic... The Emden differential equation is one of the most widely studied and challenging nonlinear dynamics equations in literature. It finds applications in various areas of study such as celestial mechanics, fluid mechanics, Steller structure, isothermal gas spheres, thermionic currents and so on. Because of the importance of the equation, the method of generalized Sundman transformation (GST) as proposed by Nakpim and Meleshko is used for linearizing the Emden differential equation. The Emden differential equation considered here is a modification of the equation given by Berkovic. The results obtained in this paper imply that the Emden equation cannot be linearized by a point transformation. The general solution of the modified Emden equation is also obtained. 展开更多
关键词 Emden Differential Equation Second Order Ordinary Differential Equation generalized Sundman transformation LINEARIZATION
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Classical and Quantum Behavior of Generalized Oscillators in Terms of Linear Canonical Transformations
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作者 Akihiro Ogura 《Journal of Modern Physics》 2016年第15期2205-2218,共14页
The quantum mechanical relationships between time-dependent oscillators, Hamilton-Jacobi theory and an invariant operator are clarified by making reference to a system with a generalized oscillator. We introduce a lin... The quantum mechanical relationships between time-dependent oscillators, Hamilton-Jacobi theory and an invariant operator are clarified by making reference to a system with a generalized oscillator. We introduce a linear transformation in position and momentum, and show that the correspondence between classical and quantum transformations is exactly one-to-one. We found that classical canonical transformations are constructed from quantum unitary transformations as long as we are concerned with linear transformations. We also show the relationship between the invariant operator and a linear transformation. 展开更多
关键词 Quantum Canonical transformation Linear transformation generalized Oscillators Invariant Operator
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Amplitude spectrum compensation and phase spectrum correction of seismic data based on the generalized S transform 被引量:6
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作者 周怀来 王峻 +3 位作者 王明春 沈铭成 张听锟 梁平 《Applied Geophysics》 SCIE CSCD 2014年第4期468-478,510,511,共13页
We propose a method for the compensation and phase correction of the amplitude spectrum based on the generalized S transform. The compensation of the amplitude spectrum within a reliable frequency range of the seismic... We propose a method for the compensation and phase correction of the amplitude spectrum based on the generalized S transform. The compensation of the amplitude spectrum within a reliable frequency range of the seismic record is performed in the S domain to restore the amplitude spectrum of reflection. We use spectral simulation methods to fit the time-dependent amplitude spectrum and compensate for the amplitude attenuation owing to absorption. We use phase scanning to select the time-, space-, and frequencydependent phases correction based on the parsimony criterion and eliminate the residual phase effect of the wavelet in the S domain. The method does not directly calculate the Q value; thus, it can be applied to the case of variable Q. The comparison of the theory model and field data verify that the proposed method can recover the amplitude spectrum of the strata reflectivity, while eliminating the effect of the residual phase of the wavelet. Thus, the wavelet approaches the zero-phase wavelet and, the seismic resolution is improved. 展开更多
关键词 generalized S transform amplitude spectra phase spectra seismic resolution phase correction
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The Fourier Transform of a Sort of Generalized Function
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作者 祝同江 《Journal of Beijing Institute of Technology》 EI CAS 1996年第2期106+101-106,共7页
The Fourier transforms of functions X ln e are given. where λ is a complex constant (λ≠-1,-2. …), a is a complex number. m=0. 1. 2,…,and
关键词 Fourier transform generalized function analytic exextension
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Generalized canonical transformation for second-order Birkhoffian systems on time scales 被引量:4
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作者 Y.Zhang X.H.Zhai 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第6期353-357,共5页
The theory of time scales,which unifies continuous and discrete analysis,provides a powerful mathematical tool for the study of complex dynamic systems.It enables us to understand more clearly the essential problems o... The theory of time scales,which unifies continuous and discrete analysis,provides a powerful mathematical tool for the study of complex dynamic systems.It enables us to understand more clearly the essential problems of continuous systems and discrete systems as well as other complex systems.In this paper,the theory of generalized canonical transformation for second-order Birkhoffian systems on time scales is proposed and studied,which extends the canonical transformation theory of Hamilton canonical equations.First,the condition of generalized canonical transformation for the second-order Birkhoffian system on time scales is established.Second,based on this condition,six basic forms of generalized canonical transformation for the second-order Birkhoffian system on time scales are given.Also,the relationships between new variables and old variables for each of these cases are derived.In the end,an example is given to show the application of the results. 展开更多
关键词 BIRKHOFFIAN systems generalized CANONICAL transformation Time scales CALCULUS generating function
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Generalized Demodulation Transform for Bearing Fault Diagnosis Under Nonstationary Conditions and Gear Noise Interferences 被引量:2
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作者 Dezun Zhao Jianyong Li +1 位作者 Weidong Cheng Zhiyang He 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第1期79-89,共11页
It is a challenging issue to detect bearing fault under nonstationary conditions and gear noise interferences. Meanwhile, the application of the traditional methods is limited by their deficiencies in the aspect of co... It is a challenging issue to detect bearing fault under nonstationary conditions and gear noise interferences. Meanwhile, the application of the traditional methods is limited by their deficiencies in the aspect of computational accuracy and e ciency, or dependence on the tachometer. Hence, a new fault diagnosis strategy is proposed to remove gear interferences and spectrum smearing phenomenon without the tachometer and angular resampling technique. In this method, the instantaneous dominant meshing multiple(IDMM) is firstly extracted from the time-frequency representation(TFR) of the raw signal, which can be used to calculate the phase functions(PF) and the frequency points(FP). Next, the resonance frequency band excited by the faulty bearing is obtained by the band-pass filter. Furthermore, based on the PFs, the generalized demodulation transform(GDT) is applied to the envelope of the filtered signal. Finally, the target bearing is diagnosed by matching the peaks in the spectra of demodulated signals with the theoretical FPs. The analysis results of simulated and experimental signal demonstrate that the proposed method is an e ective and reliable tool for bearing fault diagnosis without the tachometer and the angular resampling. 展开更多
关键词 Bearing fault diagnosis generalized DEMODULATION transform NONSTATIONARY CONDITIONS Gear noise
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An integrable generalization of the Fokas–Lenells equation:Darboux transformation, reduction and explicit soliton solutions
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作者 魏姣 耿献国 王鑫 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期117-124,共8页
Under investigation is an integrable generalization of the Fokas–Lenells equation, which can be derived from the negative power flow of a 2 × 2 matrix spectral problem with three potentials. Based on the gauge t... Under investigation is an integrable generalization of the Fokas–Lenells equation, which can be derived from the negative power flow of a 2 × 2 matrix spectral problem with three potentials. Based on the gauge transformation of the matrix spectral problem, one kind of Darboux transformation with multi-parameters for the three-component coupled Fokas–Lenells system is constructed. As a reduction, the N-fold Darboux transformation for the generalized Fokas–Lenells equation is obtained, from which the N-soliton solution in a compact Vandermonde-like determinant form is given. Particularly,the explicit one-and two-soliton solutions are presented and their dynamical behaviors are shown graphically. 展开更多
关键词 Darboux transformation soliton solutions generalized Fokas–Lenells equation
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A Protection Method of VSC-HVDC Cables Based on Generalized S-Transform 被引量:2
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作者 Weishi Man Xiaoman Bei Zhiyu Zhang 《Energy and Power Engineering》 2021年第4期1-10,共10页
<div style="text-align:justify;"> Generalized S-transform is a time-frequency analysis method which has higher resolution than S-transform. It can precisely extract the time-amplitude characteristics o... <div style="text-align:justify;"> Generalized S-transform is a time-frequency analysis method which has higher resolution than S-transform. It can precisely extract the time-amplitude characteristics of different frequency components in the signal. In this paper, a novel protection method for VSC-HVDC (Voltage source converter based high voltage DC) based on Generalized S-transform is proposed. Firstly, extracting frequency component of fault current by Generalized S-transform and using mutation point of high frequency to determine the fault time. Secondly, using the zero-frequency component of fault current to eliminate disturbances. Finally, the polarity of sudden change currents in the two terminals is employed to discriminate the internal and external faults. Simulations in PSCAD/EMTDC and MATLAB show that the proposed method can distinguish faults accurately and effectively. </div> 展开更多
关键词 generalized S-transform VSC-HVDC Phase-Mode transformation DC Cable Protection
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High-frequency compensation for seismic data based on adaptive generalized S transform 被引量:2
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作者 Li Hui-Feng Wang Jin +1 位作者 Wei Zheng-Rong Yang Fei-Long 《Applied Geophysics》 SCIE CSCD 2020年第5期747-755,902,共10页
The low-pass fi ltering eff ect of the Earth results in the absorption and attenuation of the high-frequency components of seismic signals by the stratum during propagation.Hence,seismic data have low resolution.Consi... The low-pass fi ltering eff ect of the Earth results in the absorption and attenuation of the high-frequency components of seismic signals by the stratum during propagation.Hence,seismic data have low resolution.Considering the limitations of traditional high-frequency compensation methods,this paper presents a new method based on adaptive generalized S transform.This method is based on the study of frequency spectrum attenuation law of seismic signals,and the Gauss window function of adaptive generalized S transform is used to fi t the attenuation trend of seismic signals to seek the optimal Gauss window function.The amplitude spectrum compensation function constructed using the optimal Gauss window function is used to modify the time-frequency spectrum of the adaptive generalized S transform of seismic signals and reconstruct seismic signals to compensate for high-frequency attenuation.Practical data processing results show that the method can compensate for the high-frequency components that are absorbed and attenuated by the stratum,thereby eff ectively improving the resolution and quality of seismic data. 展开更多
关键词 seismic data time-frequency analysis adaptive generalized S transform high-frequency compensation
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New Generalized Transformation Method and Its Application in Higher-Dimensional Soliton Equation 被引量:2
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作者 BAI Cheng-Lin GUO Zong-Lin ZHAO Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期447-451,共5页
A new generalized transformation method is differential equation. As an application of the method, we presented to find more exact solutions of nonlinear partial choose the (3+1)-dimensional breaking soliton equati... A new generalized transformation method is differential equation. As an application of the method, we presented to find more exact solutions of nonlinear partial choose the (3+1)-dimensional breaking soliton equation to illustrate the method. As a result many types of explicit and exact traveling wave solutions, which contain solitary wave solutions, trigonometric function solutions, Jacobian elliptic function solutions, and rational solutions, are obtained. The new method can be extended to other nonlinear partial differential equations in mathematical physics. 展开更多
关键词 new generalized transformation method exact solution (3+1)-dimensional breaking soliton equation KdV equation mKdV equation cubic nonlinear Klein-Gordon equation
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GENERALIZED WAVELETS AND INVERSION OF THE RADON TRANSFORM ON THE LAGUERRE HYPERGROUP 被引量:1
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作者 Bai Linglan He Jianxun (Nanjing Normal University, China) 《Approximation Theory and Its Applications》 2002年第4期55-69,共15页
Let X=Rn +×R denote the underlying manifold of polyradial functions on the Heisenberg group H n. We construct a generalized translation on X=Rn +×R, and establish the Plancherel formula on L2(X,dμ). Usin... Let X=Rn +×R denote the underlying manifold of polyradial functions on the Heisenberg group H n. We construct a generalized translation on X=Rn +×R, and establish the Plancherel formula on L2(X,dμ). Using the Gelfand transform we give the condition of generalized wavelets on L2(X,dμ). Moreover, we show the reconstruction formulas for wavelet packet trnasforms and an inversion formula of the Radon transform on X. 展开更多
关键词 MATH generalized WAVELETS AND INVERSION OF THE RADON transform ON THE LAGUERRE HYPERGROUP
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Certain Integral Transforms of Generalized k-Bessel Function
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作者 Kottakkaran Sooppy Nisar Waseem Ahmad Khan Mohd Ghayasuddin 《Analysis in Theory and Applications》 CSCD 2018年第2期165-174,共10页
The objective of this note is to provide some(potentially useful) integral transforms(for example, Euler, Laplace, Whittaker etc.) associated with the generalized k-Bessel function defined by Saiful and Nisar [3]. We ... The objective of this note is to provide some(potentially useful) integral transforms(for example, Euler, Laplace, Whittaker etc.) associated with the generalized k-Bessel function defined by Saiful and Nisar [3]. We have also discussed some other transforms as special cases of our main results. 展开更多
关键词 GAMMA FUNCTION k-Bessel FUNCTION generalized k-Bessel FUNCTION INTEGRAL transforms
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Enhancing the resolution of seismic data based on the generalized S-transform 被引量:3
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作者 Tian Jianhua Song Wei Yang Feizhou 《Petroleum Science》 SCIE CAS CSCD 2009年第2期153-157,共5页
In this paper, we analyze the seismic signal in the time-frequency domain using the generalized S-transform combined with spectrum modeling. Without assuming that the reflection coefficients are random white noise as ... In this paper, we analyze the seismic signal in the time-frequency domain using the generalized S-transform combined with spectrum modeling. Without assuming that the reflection coefficients are random white noise as in the conventional resolution-enhanced techniques, the wavelet which changes with time and frequency was simulated and eliminated. After using the inverse S-transform for the processed instantaneous spectrum, the signal in the time domain was obtained again with a more balanced spectrum and broader frequency band. The quality of seismic data was improved without additional noise. 展开更多
关键词 Time-frequency domain generalized S-transform spectrum modeling instantaneous spectrum balanced spectrum
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Intelligent Transformation: General Intelligence Theory
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作者 Alexander Ngu Amaya Odilon Kosso 《International Journal of Intelligence Science》 2024年第3期59-70,共12页
This paper aims to formalize a general definition of intelligence beyond human intelligence. We accomplish this by re-imagining the concept of equality as a fundamental abstraction for relation. We discover that the c... This paper aims to formalize a general definition of intelligence beyond human intelligence. We accomplish this by re-imagining the concept of equality as a fundamental abstraction for relation. We discover that the concept of equality = limits the sensitivity of our mathematics to abstract relationships. We propose a new relation principle that does not rely on the concept of equality but is consistent with existing mathematical abstractions. In essence, this paper proposes a conceptual framework for general interaction and argues that this framework is also an abstraction that satisfies the definition of Intelligence. Hence, we define intelligence as a formalization of generality, represented by the abstraction ∆∞Ο, where each symbol represents the concepts infinitesimal, infinite, and finite respectively. In essence, this paper proposes a General Language Model (GLM), where the abstraction ∆∞Ο represents the foundational relationship of the model. This relation is colloquially termed “The theory of everything”. 展开更多
关键词 INTELLIGENCE generALIZATION ABSTRACTION transformATION general Language Model general Intelligence Theory Theory of Everything
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A generalized Hadamard transformation from new entangled state
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作者 徐兴磊 徐世民 +2 位作者 张运海 李洪奇 王继锁 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期105-109,共5页
A new entangled state |η 0) is proposed by the technique of integral within an ordered product. A generalized Hadamaxd transformation is derived by virtue of η; θ), which plays a role of Hadamard transformation ... A new entangled state |η 0) is proposed by the technique of integral within an ordered product. A generalized Hadamaxd transformation is derived by virtue of η; θ), which plays a role of Hadamard transformation for (a1 sinθ - a2 cosθ) and (a1 cosθ + a2 sin θ). 展开更多
关键词 generalized Hadamard transformation entangled state technique of integral within an ordered product
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