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HNN是一类基于物理先验学习哈密尔顿系统的神经网络.本文通过误差分析解释使用不同积分器作为超参数对HNN的影响.如果我们把网络目标定义为在任意训练集上损失为零的映射,那么传统的积分器无法保证HNN存在网络目标.我们引进反修正方程,并严格证明基于辛格式的HNN具有网络目标,且它与原哈密尔顿量之差依赖于数值格式的精度.数值实验表明,由辛HNN得到的哈密尔顿系统的相流不能精确保持原哈密尔顿量,但保持网络目标;网络目标在训练集、测试集上的损失远小于原哈密尔顿量的损失;在预测问题上辛HNN较非辛HNN具备更强大的泛化能力和更高的精度.因此,辛格式对于HNN是至关重要的. 相似文献
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A series of non-Noether conservative quantities and Mei symmetries of nonconservative systems 下载免费PDF全文
In this paper Mei symmetry is introduced for a nonconservative system. The necessary and
sufficient condition for a Mei symmetry to be also a Lie symmetry is
derived. It is proved that the Mei symmetry leads to a non-Noether
conservative quantity via a Lie symmetry, and deduces a Lutzky conservative
quantity via a Lie point symmetry. 相似文献
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The algebraic structure and Poisson's integral theory of mechanico-electrical
systems are studied. The Hamilton canonical equations and generalized Hamilton
canonical equations and their the contravariant algebraic forms for
mechanico-electrical systems are obtained. The Lie algebraic structure and the
Poisson's integral theory of Lagrange mechanico-electrical systems are derived. The
Lie algebraic structure admitted and Poisson's integral theory of the
Lagrange--Maxwell mechanico-electrical systems are presented. Two examples are
presented to illustrate these results. 相似文献
4.
A discrete total variation calculus with variable time steps is
presented for mechanico-electrical systems where there exist
non-potential and dissipative forces. By using this discrete
variation calculus, the symplectic-energy-first integrators for
mechanico-electrical systems are derived. To do this, the time step
adaptation is employed. The discrete variational principle and the
Euler--Lagrange equation are derived for the systems. By using this
discrete algorithm it is shown that mechanico-electrical systems are
not symplectic and their energies are not conserved unless they are
Lagrange mechanico-electrical systems. A practical example is
presented to illustrate these results. 相似文献
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Noether conserved quantities and Lie point symmetries of difference Lagrange--Maxwell equations and lattices 下载免费PDF全文
This paper presents a method to find Noether-type conserved quantities and Lie point symmetries for discrete mechanico-electrical dynamical systems, which leave invariant the set of solutions of the corresponding difference scheme. This
approach makes it possible to devise techniques for solving the Lagrange--Maxwell equations in differences which correspond to mechanico-electrical systems, by adapting existing differential equations. In particular, it obtains a new systematic method to determine both the one-parameter Lie groups and the discrete Noether conserved quantities of Lie point symmetries for mechanico-electrical systems. As an application, it obtains the Lie point symmetries and the conserved quantities for the difference equation of a model that represents a capacitor microphone. 相似文献
7.
This paper introduces the concept of
hierarchical-control-based output synchronization of coexisting
attractor networks. Within the new framework, each dynamic node is
made passive at first utilizing intra-control around its own arena.
Then each dynamic node is viewed as one agent, and on account of
that, the solution of output synchronization of coexisting attractor
networks is transformed into a multi-agent consensus problem, which
is made possible by virtue of local interaction between individual
neighbours; this distributed working way of coordination is coined
as inter-control, which is only specified by the topological
structure of the network. Provided that the network is connected and
balanced, the output synchronization would come true naturally via
synergy between intra and inter-control actions, where the
rightness is proved theoretically via convex composite Lyapunov
functions. For completeness, several illustrative examples are
presented to further elucidate the novelty and efficacy of the
proposed scheme. 相似文献
8.
Non-Noether symmetries and Lutzky conservative quantities of nonholonomic nonconservative dynamical systems 下载免费PDF全文
Non-Noether symmetries and conservative quantities of nonholonomic nonconservative dynamical systems are investigated in this paper. Based on the relationships among motion, nonconservative forces, nonholonomic constrained forces and Lagrangian, non-Noether symmetries and Lutzky conservative quantities are presented for nonholonomic nonconservative dynamical systems. The relation between non-Noether symmetry and Noether symmetry is discussed and it is further shown that non-Noether conservative quantities can be obtained by a complete set of Noether invariants. Finally,an example is given to illustrate these results. 相似文献
9.
Discrete variational principle and first integrals for Lagrange--Maxwell mechanico-electrical systems 下载免费PDF全文
This paper presents a discrete variational principle and a method to
build first-integrals for finite dimensional Lagrange--Maxwell
mechanico-electrical systems with nonconservative forces and a
dissipation function. The discrete variational principle and the
corresponding Euler--Lagrange equations are derived from a discrete
action associated to these systems. The first-integrals are obtained
by introducing the infinitesimal transformation with respect to the
generalized coordinates and electric quantities of the systems. This
work also extends discrete Noether symmetries to mechanico-electrical
dynamical systems. A practical example is presented to illustrate the
results. 相似文献
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