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The Hamiltonian Structures of 3D ODE with Time-Independent Invariants
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作者 郭仲衡 陈玉明 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第4期301-306,共6页
We have proved that any 3-dimensional dynamical system of ordinary differentialequations(in short, 3D ODE)With time-independent invariants can be rewritten asHaniltonian systems with respect to generalized Poisson bra... We have proved that any 3-dimensional dynamical system of ordinary differentialequations(in short, 3D ODE)With time-independent invariants can be rewritten asHaniltonian systems with respect to generalized Poisson brackets and theHamiltonians are these invariants. As an example,we discuss the Kermack-Mckendrick modelfor epidemics in detail. The results we obtained are generalizatioof those obtained by Y. Nutku. 展开更多
关键词 Poisson bracket Hamiltonian structure bi-Hamiltonianstructure. invariant. the Kermack-Mckendrick model forepidem ics
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Left-Right Non-Linear Dynamical Higgs
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作者 Jing Shu Juan Yepes 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第12期643-662,共20页
All the possible CP-conserving non-linear operators up to the p^4-order in the Lagrangian expansion are analysed here for the left-right symmetric model in the non-linear electroweak chiral context coupled to a light ... All the possible CP-conserving non-linear operators up to the p^4-order in the Lagrangian expansion are analysed here for the left-right symmetric model in the non-linear electroweak chiral context coupled to a light dynamical Higgs. The low energy effects will be triggered by an emerging new physics field content in the nature, more specifically,from spin-1 resonances sourced by the straightforward extension of the SM local gauge symmetry to the larger local group SU(2)_L × SU(2)_R× U(1)_(B-L). Low energy phenomenology will be altered by integrating out the resonances from the physical spectrum, being manifested through induced corrections onto the left handed operators. Such modifications are weighted by powers of the scales ratio implied by the symmetries of the model and will determine the size of the effective operator basis to be used. The recently observed diboson excess around the invariant mass 1.8 TeV–2 TeV entails a scale suppression that suggests to encode the low energy effects via a much smaller set of effective operators. 展开更多
关键词 left-right model nonlinear invariance CP symmetry SU(2)×SU(2)×U(1) effective Lagrangian Higgs couplings
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Method to generate training samples for neural network used in target recognition
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作者 何灏 罗庆生 +2 位作者 罗霄 徐如强 李钢 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期400-407,共8页
Training neural network to recognize targets needs a lot of samples.People usually get these samples in a non-systematic way,which can miss or overemphasize some target information.To improve this situation,a new meth... Training neural network to recognize targets needs a lot of samples.People usually get these samples in a non-systematic way,which can miss or overemphasize some target information.To improve this situation,a new method based on virtual model and invariant moments was proposed to generate training samples.The method was composed of the following steps:use computer and simulation software to build target object's virtual model and then simulate the environment,light condition,camera parameter,etc.;rotate the model by spin and nutation of inclination to get the image sequence by virtual camera;preprocess each image and transfer them into binary image;calculate the invariant moments for each image and get a vectors' sequence.The vectors' sequence which was proved to be complete became the training samples together with the target outputs.The simulated results showed that the proposed method could be used to recognize the real targets and improve the accuracy of target recognition effectively when the sampling interval was short enough and the circumstance simulation was close enough. 展开更多
关键词 pattern recognition training samples for neural network model emulation space coordinate transform invariant moments
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The J_2 invariant relative configuration of spaceborne SAR interferometer for digital elevation measurement
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作者 Ming Xu Ying-Hong Jia Shi-Jie Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第4期643-651,共9页
A 3-craft formation configuration is proposed to perform the digital elevation model (DEM) for the distributed spacebome interferometric synthetic aperture radar (InSAR), and it is optimized by the modified ant co... A 3-craft formation configuration is proposed to perform the digital elevation model (DEM) for the distributed spacebome interferometric synthetic aperture radar (InSAR), and it is optimized by the modified ant colony algorithm to have the best compatibility with J2 invariant orbits created by differential correction algorithm. The configuration has succeeded in assigning the across-track baseline to vary periodically and with its mean value equal to the optimal baseline determined by the relative height measurement accuracy. The required relationship between crafts' magnitudes and phases is formulated for the general case of interferometry measure from non-orthographic and non-lateral view. The J2 invariant configurations created by differential correction algorithm are employed to investigate their compatibility with the required configuration. The colony algorithm is applied to search the optimal configuration holding the near-constant across-track baseline under the J2 perturbation, and the absolute height measurement accuracy is preferable as expected. 展开更多
关键词 InSAR Digital elevation model (DEM) J2 invariant orbit Differential correction algorithm Formation flying
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Binding Energy, Root Mean Square Radius and Magnetic Dipole Moment of the Triton Nucleus
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作者 Khadija Abdelhassan Kharroube 《Open Journal of Microphysics》 2024年第2期24-39,共16页
The basis functions of the translation invariant shell model are used to construct the ground state nuclear wave functions of <sup>3</sup>H. The used residual two-body interactions consist of central, tens... The basis functions of the translation invariant shell model are used to construct the ground state nuclear wave functions of <sup>3</sup>H. The used residual two-body interactions consist of central, tensor, spin orbit and quadratic spin orbit terms with Gaussian radial dependence. The parameters of these interactions are so chosen in such a way that they represent the long-range attraction and the short-range repulsion of the nucleon-nucleon interactions. These parameters are so chosen to reproduce good agreement between the calculated values of the binding energy, the root mean-square radius, the D-state probability, the magnetic dipole moment and the electric quadrupole moment of the deuteron nucleus. The variation method is then used to calculate the binding energy of triton by varying the oscillator parameter which exists in the nuclear wave function. The obtained nuclear wave functions are then used to calculate the root mean-square radius and the magnetic dipole moment of the triton. 展开更多
关键词 Translation Invariant Shell model Residual Two-Body Interactions Nucleon-Nucleon Interactions Binding Energy Nuclear Wave Functions
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Binding Energy, Root-Mean Square Radius and Magnetic Dipole Moment of the Nucleus 6Li
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作者 Khadija Abdelhassan Kharroube 《Open Journal of Microphysics》 2024年第4期89-101,共13页
In this work, we have applied the translation invariant shell model with number of quanta of excitations N=2,4,6,8and 10 to define the ground-state eigenenergies and their corresponding normalized eigenstates, the roo... In this work, we have applied the translation invariant shell model with number of quanta of excitations N=2,4,6,8and 10 to define the ground-state eigenenergies and their corresponding normalized eigenstates, the root mean-square radius, and the magnetic dipole moment of the nucleus 6Li. We have computed the necessary two-particle orbital fractional parentage coefficients for nuclei with mass number A=6and number of quanta of excitations N=10, which are not available in the literature. In addition, we have used our previous findings on the nucleon-nucleon interaction with Gaussian radial dependencies, which fits the deuteron characteristics as well as the triton binding energy, root-mean square radius and magnetic dipole moment. The numerical results obtained in this work are in excellent agreement with the corresponding experimental data and the previously published theoretical results in the literature. 展开更多
关键词 Nuclear Structure The Nucleus 6Li The Translation Invariant Shell model Binding Energy Root-Mean Square Radius Magnetic Dipole Moment
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Invariant line and crystallography of HCP→BCC precipitation
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作者 肖晓玲 罗承萍 刘江文 《Science China(Technological Sciences)》 SCIE EI CAS 2002年第1期58-64,共7页
The method of calculating the invariant line in HCP→BCC precipitation based on the invariant line strain model is described. The experimentally determined crystallographic features of the lath-shaped or needle-like p... The method of calculating the invariant line in HCP→BCC precipitation based on the invariant line strain model is described. The experimentally determined crystallographic features of the lath-shaped or needle-like precipitates formed in the HCP→BCC precipitations occurring in Mg?Al and Zr?Nb alloys were found to be in excellent agreement with the predictions from the model, thus suggesting that the model is valid for predicting the crystallography of diffusion-controlled phase transformations. 展开更多
关键词 HCP→BCC precipitation invariant line invariant line strain model CRYSTALLOGRAPHY
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Transition Distributions of Young Diagrams Under Periodically Weighted Plancherel Measures
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作者 Zhong-gen Su 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2009年第4期655-674,共20页
Kerov[16,17] proved that Wigner's semi-circular law in Gauss[an unitary ensembles is the transition distribution of the omega curve discovered by Vershik and Kerov[34] for the limit shape of random partitions under t... Kerov[16,17] proved that Wigner's semi-circular law in Gauss[an unitary ensembles is the transition distribution of the omega curve discovered by Vershik and Kerov[34] for the limit shape of random partitions under the Plancherel measure. This establishes a close link between random Plancherel partitions and Gauss[an unitary ensembles, In this paper we aim to consider a general problem, namely, to characterize the transition distribution of the limit shape of random Young diagrams under Poissonized Plancherel measures in a periodic potential, which naturally arises in Nekrasov's partition functions and is further studied by Nekrasov and Okounkov[25] and Okounkov[28,29]. We also find an associated matrix mode[ for this transition distribution. Our argument is based on a purely geometric analysis on the relation between matrix models and SeibergWitten differentials. 展开更多
关键词 Limit shape Limiting density of eigenvalues Poissonized Plancherel measures in a periodic potential Transition distributions Unitary invariant matrix models
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