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20022024
most citedMathematical Modeling of COVID-19 Transmission Dynamics with a Case Study of Wuhan

731 citations · 12.8k across the 413 of their papers we have counts for

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Showing 2003Show all

6 papers · 1 filter

math.HO2003

Smarandache Sequences: Explorations and Discoveries with a Computer Algebra System

Paulo D. F. Gouveia, Delfim F. M. Torres

We study Smarandache sequences of numbers, and related problems, via a Computer Algebra System. Solutions are discovered, and some conjectures presented.

math.OC2003

On the Constancy of the Pontryagin Hamiltonian for Autonomous Problems

Delfim F. M. Torres

We provide a new, simpler, and more direct proof of the well known fact that for autonomous optimal control problems the Pontryagin extremals evolve on a level surface of the respe…

math.OC2003★ 26 cited

Quasi-Invariant Optimal Control Problems

Delfim F. M. Torres

We study in optimal control the important relation between invariance of the problem under a family of transformations, and the existence of preserved quantities along the Pontryag…

math.OC2003

A Proper Extension of Noether's Symmetry Theorem for Nonsmooth Extremals of the Calculus of Variations

Delfim F. M. Torres

For nonsmooth Euler-Lagrange extremals, Noether's conservation laws cease to be valid. We show that Emmy Noether's theorem of the calculus of variations is still valid in the wider…

math.OC2003

Integrals of Motion for Discrete-Time Optimal Control Problems

Delfim F. M. Torres

We obtain a discrete time analog of E. Noether's theorem in Optimal Control, asserting that integrals of motion associated to the discrete time Pontryagin Maximum Principle can be…

math.OC2003★ 9 cited

Gauge Symmetries and Noether Currents in Optimal Control

Delfim F. M. Torres

We extend the second Noether theorem to optimal control problems which are invariant under symmetries depending upon k arbitrary functions of the independent variable and their der…